scenario questions

A junior administrator reports that users cannot connect to a file server running Samba. The server is reachable via ping. Logs from the Samba service show: 'smbd: error while loading shared libraries: libgnutls.so.30: cannot open shared object file: No such file or directory'. The administrator confirms the package 'libgnutls' is installed. Which of the following is the most likely cause and solution?

An administrator is managing a Kubernetes cluster. A pod is running but not responding as expected. The administrator wants to view the standard output logs from the pod's main container. Which kubectl command should be used?

An administrator wants to monitor disk I/O performance in real-time, focusing on metrics like wait time and I/O queue size. Which tool is best suited for this?

A Linux administrator needs a cron job that runs /usr/local/bin/collect.sh at 02:30 every Monday, Wednesday, and Friday. The job must be added for the root user without editing the global /etc/crontab file. Which command should the administrator run to open the correct crontab for editing?

A technician needs to check the kernel ring buffer for hardware errors detected during system boot. Which command should be used?

A Linux administrator needs to extract the value of the 'version' field from a JSON file named config.json. The file contains a top-level key 'version' with a string value. Which command should be used to retrieve just the value?

An organization uses Kubernetes to deploy containerized applications. A pod fails to start with an ImagePullBackOff error. What is the most likely cause?

A junior Linux administrator needs to run a long-running backup script as the user 'backupuser' but currently has an active SSH session as 'adminuser'. The script should continue running even if the SSH session disconnects, and no output should be sent to the terminal. Which command should the administrator use?

A system administrator is troubleshooting a custom systemd service that fails to start. Which of the following commands should be used to diagnose the issue? (Choose two.)

A system administrator is writing a Bash script that must check if a file exists and is readable. Which two test expressions can be used to achieve this? (Choose two.)

An Ansible playbook includes a handler that restarts a service when a configuration file is changed. Which directive in a task triggers the handler?

After a power failure, a Linux server boots into emergency mode. The system logs indicate an unclean filesystem on /dev/sda2. Which command should the administrator run to repair the filesystem?

A Linux administrator needs to change the runlevel of a systemd-based system to a state where only a single user can log in for maintenance, without starting network services. Which systemd target should the administrator use?

A Linux administrator schedules a maintenance script with cron using the entry `30 2 * * 1 /usr/local/bin/backup.sh`. The script runs but produces no output and fails silently when executed by cron, though it works when run interactively. Which action best addresses the silent failure?

An administrator needs to allow a user to run all commands as root without a password. Which sudoers entry accomplishes this?

A container is running a web server on port 8080 internally, and the administrator wants to access it on the host on port 80. Which Docker run option accomplishes this?

A system administrator wants to create a bind mount in Docker to share a host directory `/data` with a container at `/mnt/data`. Which of the following docker run options should be used?

An administrator wants to replace all occurrences of 'oldstring' with 'newstring' in a configuration file named config.cfg, and save the changes. Which sed command should be used?

A user wants to run a Docker container in detached mode, remove it automatically after it stops, and map host port 8080 to container port 80. Which command accomplishes this?

A system administrator wants to change the priority of a running process with PID 1234 to a lower priority (higher nice value). Which command should be used?

Based on the exhibit, what is the most likely cause of the 'PV Status: not available'?

A developer is writing a Bash script that must be portable across different Linux distributions. The script needs to check if a package is installed. Which command should be used to achieve this portability?

A Linux administrator is preparing a new server that uses systemd-boot as the boot loader. The administrator wants to verify the current boot loader entries and their order. Which command should the administrator run?

An application running under an AppArmor profile is being denied access to log files. The administrator wants to troubleshoot by allowing all actions and logging denials. Which command will switch the profile to complain mode?

A file named 'webapp.conf' is being served by Apache but users get a 'Permission denied' error. The SELinux context of the file is 'unconfined_u:object_r:admin_home_t:s0'. What is the most appropriate command to fix the SELinux context?

A Linux administrator wants to ensure a bash script stops execution immediately if any command fails. Which line should be added to the script?

A Linux administrator is packaging an internal automation tool as a container image and must ensure the resulting image is minimal, reproducible, and does not include a shell or package manager. Which TWO practices best support that goal? (Choose two.)

Which file contains the password aging information such as minimum and maximum days between password changes?

A security analyst needs to see a list of failed login attempts on a Linux system. Which command displays this information from the /var/log/btmp log?

A Linux administrator needs to check which services are listening on TCP port 22. Which command should be used?

Which command is used to display the contents of the systemd journal for a specific unit?

Which TWO of the following are characteristics of containers compared to virtual machines? (Choose two.)

A user reports that the /home partition is running out of space. Which command identifies the largest directories under /home?

A security policy requires that system logs be rotated weekly and kept for 4 weeks. Which configuration file should be modified to achieve this for /var/log/syslog?

Based on the exhibit, what is the purpose of the audit rule?

A server shows /dev/sda1 mounted at / is 100% full in df -h, but du -sh / shows only 50% usage. What is the most likely explanation?

An administrator needs to schedule a backup script to run every Monday at 2:00 AM. Which crontab entry will accomplish this?

An administrator needs to extend the size of a logical volume named 'lv_data' in volume group 'vg_data' by 10 GB. A new disk /dev/sdb has been added to the system. What is the correct sequence of commands?

A Linux administrator is configuring a systemd timer to run a maintenance script daily. The administrator creates maint.service and maint.timer unit files, then runs systemctl start maint.timer. The script does not run at the expected time. Which command should the administrator run to enable the timer so it starts automatically at boot and triggers on schedule?

Which of the following is a key difference between Docker and Podman?

Refer to the exhibit. A developer is pushing an image to a private registry at `192.168.1.100:5000` but receives an error about using an insecure registry. Which part of the Docker daemon configuration allows this registry without TLS?

A developer needs to run a one-time script after the network is up on a systemd-based server. Which unit type should be used?

A Linux administrator needs to locate all files in the /var/log directory that have been modified within the last 2 days and contain the word 'error' (case-insensitive). Which command accomplishes this?

An administrator wants to use Ansible to ensure a service is running on a remote host. Which Ansible module should be used in a playbook?

A system administrator wants to limit the number of simultaneous logins for a user to 2. Which file and parameter should be configured?

A technician wants to create a symbolic link in /usr/local/bin that points to /opt/myapp/bin/start.sh. The technician has write permissions to /usr/local/bin. Which command should be used?

A system administrator wants to encrypt a large directory of files using GPG with a symmetric cipher. Which two steps are necessary? (Select TWO).

A user reports they cannot log in after three failed password attempts. The system uses PAM with pam_faillock. Which command can the administrator use to view the number of failed attempts for the user?

A Linux administrator needs to view real-time information about running processes, including CPU and memory usage. Which TWO commands can be used for this purpose? (Choose two.)

A Linux server reports that its root filesystem is 100 percent full, and applications are failing to write logs. The administrator needs to identify what is consuming space and reclaim it safely. Which two commands are appropriate to determine where the space is used? (Choose two.)

Which TWO commands can be used to check disk space usage on a Linux system?

A system administrator wants to review kernel-related log messages from the current boot session. Which journalctl command should be used to filter the kernel messages?

A Linux server is configured with an IPsec VPN using strongSwan. The administrator needs to verify that the VPN tunnel is active and that traffic is being encrypted. Which command should be used to display the current status of the IPsec security associations?

Based on the exhibit, what is the most likely cause of the repeated connection refused errors?

A DevOps engineer is creating a Podman container that needs to communicate with a host service listening on a Unix socket at /run/host-service.sock. Which of the following mount options will make the socket available inside the container?

A technician needs to kill a process with PID 1234 that is not responding to normal termination. Which command sends SIGKILL?

Which of the following directories in the Filesystem Hierarchy Standard (FHS) contains variable data files such as logs, spool files, and temporary files that persist across reboots?

An administrator needs to create a Docker image from a Dockerfile located in the current directory and tag it as 'myapp:v1'. Which command should be used?

A security analyst notices repeated failed login attempts on a Linux server. They want to lock the account after 3 failed attempts using PAM. Which PAM module should be configured in /etc/pam.d/sshd or /etc/pam.d/system-auth?

A technician wants to extract the third column of a tab-separated file and sort the output uniquely. Which three commands can be combined using pipes to achieve this? (Choose three.)

A Linux administrator uses Ansible to manage a fleet of servers and needs to ensure a configuration file is present with specific contents on all web servers, restarting the service only when the file changes. Which Ansible module and handler pattern accomplishes this?

A Linux system is running slowly with high I/O wait as shown by vmstat. To investigate the I/O activity of a specific process that is suspected of causing the bottleneck, which of the following commands would be used to trace its system calls related to I/O?

A security audit reveals that a Linux system allows password-based SSH logins and has weak password policies. Which THREE actions should the administrator take to improve security? (Choose three.)

A server with multiple disks is configured with RAID 5 for performance and redundancy. The administrator notices that write performance is lower than expected. Which RAID level would provide better write performance while still offering fault tolerance with the same number of disks (minimum 4)?

A Linux administrator needs to schedule a script to run every Monday at 3:00 AM. The script is located at /usr/local/bin/backup.sh. The administrator wants to use a systemd timer instead of cron. Which pair of files is required to implement this?

After applying a kernel update, a Linux server boots but the root filesystem is mounted read-only, and dmesg shows I/O errors on /dev/sda2. The administrator needs to determine whether the filesystem is corrupted and, if so, repair it safely. Which sequence of actions should the administrator take?

During boot, a Linux system displays a kernel panic with the message 'VFS: Unable to mount root fs on unknown-block(0,0)'. Which of the following is the most likely cause?

A server running nftables has a rule set that allows incoming SSH from the management network (192.168.1.0/24). An administrator needs to insert a rule to drop SSH from all other sources. Which nft command accomplishes this? Assume the input chain is 'input' and the table is 'inet filter'.

A Linux administrator is configuring a server to use firewalld. The administrator wants to allow incoming traffic on TCP port 8080 only from the 192.168.1.0/24 subnet, while denying it from all other sources, without affecting other services. Which firewalld command should the administrator use to achieve this?

The system is experiencing slow disk I/O. Based on the exhibit, which step should the administrator take to improve performance?

An organization is migrating from a legacy automation tool to Ansible. Which of the following best describes the role of Ansible playbooks in configuration management?

A bash script uses a loop to iterate over files in a directory. Which TWO of the following loop constructs will correctly iterate over each .txt file in the current directory? (Select TWO).

A company is deploying a new web application using Docker containers. The application requires configuration values that vary between environments (development, staging, production). Which approach ensures the configuration is securely managed and applied without modifying the container image?

An administrator needs to harden SSH access. Which TWO settings in /etc/ssh/sshd_config are recommended to improve security? (Choose two.)

A Linux technician is troubleshooting a system that is experiencing high disk I/O wait times. Which TWO commands can be used to identify disk I/O performance issues? (Choose two.)

A service called 'myapp' fails to start automatically after a system reboot. The administrator wants to ensure the service starts at boot. Which systemctl command should be used?

A company runs a critical web application on a single server using Docker containers. The application consists of a web frontend container and a backend API container. Recently, the server ran out of disk space due to Docker logs and temporary images. The sysadmin is tasked with automating cleanup to prevent recurrence. The solution must not disrupt running containers. Which approach should be taken?

A system fails to boot with a kernel panic. The administrator wants to recover by accessing a root shell. Which THREE methods can be used to achieve this?

An administrator needs to schedule a backup script located at '/usr/local/bin/backup.sh' to run every Sunday at 2:30 AM. The server uses cron for task scheduling. The administrator currently has the following crontab entry: '30 2 * * 0 /usr/local/bin/backup.sh'. However, the administrator wants to verify that the cron job is configured correctly and will run as expected. Which of the following commands should the administrator use to list the current user's cron jobs and verify the entry?

Match each Linux package manager to its distribution family.

A Linux administrator needs to ensure that all user passwords meet a minimum length of 12 characters and include at least one uppercase letter, one lowercase letter, one digit, and one special character. Which file should be edited to enforce these password complexity requirements?

A server fails to boot with a kernel panic after a system update. The administrator suspects a corrupt initramfs. Which GRUB boot parameter should be added temporarily to boot into an emergency shell where the filesystem can be repaired?

A technician needs to check the current memory usage on a Linux system, including buffers and cache. Which command provides the most user-friendly output?

A Linux administrator needs to locate all files in /var/log that were modified more than 7 days ago. Which command should be used?

An administrator is troubleshooting a service that fails to start. They want to trace the system calls made by the service binary. Which command should they use?

Refer to the exhibit. A Docker container using a bind mount fails to start with a permission error. What is the most likely cause?

A Linux administrator needs to add a new user named 'jdoe' with a home directory and a bash shell. Which command accomplishes this?

A Linux administrator is troubleshooting a service that fails to start. The service's unit file has a dependency on another service, but the dependent service is not running. The administrator wants to view the dependency tree of the failing service to understand the ordering and requirements. Which command should be used?

A system administrator needs to install a package from a local RPM file without resolving dependencies automatically. Which command should be used?

A Linux administrator needs to parse a structured configuration file and extract the value of a specific key. The file format is JSON, and the administrator wants to use a command-line tool that is commonly preinstalled on modern Linux distributions. Which command should the administrator use?

Drag and drop the steps to mount a new filesystem in the correct order.

A company requires that all systems be configured to log all authentication attempts, both successful and failed. Which configuration file and directive should be used to ensure all auth messages are logged to /var/log/secure?

An administrator needs to prevent a specific user 'bob' from logging in via SSH while allowing other users. Which configuration directive should be added to /etc/ssh/sshd_config?

A Bash script contains the following line: set -e. What is the effect of this command?

A Linux administrator is investigating why a scheduled backup job did not run overnight. The job is defined in the root user's crontab. Which command should the administrator use to review the cron daemon's log entries for the relevant time period?

In bash, what is the difference between single quotes and double quotes?

A new employee needs a user account on a Linux server. The administrator runs 'useradd -m jdoe' and then 'passwd jdoe'. After setting the password, the employee reports that they cannot log in via SSH. The administrator verifies the password is correct. Which file should the administrator check to ensure the account is not locked?

A user reports that a service fails to start with the error 'Permission denied'. The service runs under a non-root user. Which command should the administrator use to check if the service has the correct file permissions?

An administrator wants to restrict SSH access to only users in the 'sshusers' group. Which configuration directive should be added to /etc/ssh/sshd_config?

A system administrator wants to view the last 10 lines of a log file and also save those lines to another file for analysis. Which command should the administrator use?

An administrator is troubleshooting a Pod in a Kubernetes cluster that is not starting. Which TWO kubectl commands are most useful for diagnosing the issue? (Choose TWO.)

A container is running a database service that requires persistent storage. The administrator wants to ensure that data persists even if the container is removed. Which volume mount type should be used in the Docker run command?

A Linux administrator is writing a Bash script that must parse command-line options, accept a required input file argument, and provide a help message when invoked with -h. The script will be run on several distributions. Which TWO practices should the administrator follow? (Choose two.)

An administrator is troubleshooting a service that fails to start. The administrator wants to view the last 50 lines of the service's journal log entries from the current boot. Which journalctl command should be used?

A Linux administrator needs to write a Bash script that runs a series of commands and stops immediately if any command fails. Which directive should be included at the beginning of the script?

Based on the exhibit, what is the most likely cause of the sshd service failure?

A Kubernetes administrator needs to expose a deployment named 'web-app' running on port 80 internally within the cluster. Which kubectl command creates a service of type ClusterIP that maps port 80 to the target port 8080 on the pods?

A Linux administrator needs to grant a user the ability to run a specific command as root without being prompted for a password, while restricting all other commands. Which file should be edited to configure this using sudo?

The output of df -h shows the root filesystem at 100% capacity. Which of the following commands should the administrator run NEXT to identify the cause?

A Linux administrator needs to grant the user 'jsmith' the ability to restart the httpd service without entering a password, while preventing all other sudo commands. The administrator creates the file /etc/sudoers.d/jsmith with the line: jsmith ALL=(root) NOPASSWD: /usr/bin/systemctl restart httpd. After saving the file, jsmith reports that sudo still prompts for a password. Which command should the administrator run to diagnose the issue?

What does the output in the exhibit indicate about the /etc/shadow file?

A Linux server hosts a web application that must be able to bind to TCP port 443. The administrator has already installed the application and configured it to listen on 443. However, when the service starts, it fails with a 'Permission denied' error. The administrator confirms that no other process is using port 443 and that the service runs as the non-root user 'webapp'. Which command should the administrator use to grant the necessary capability to the service binary without giving it full root privileges?

A Docker container is running in the background. Which command allows the administrator to execute an interactive bash shell inside the running container named 'webapp'?

A Linux administrator needs to ensure that a new service, `myapp.service`, starts automatically at boot and is also started immediately, without rebooting. The service unit file is already installed in `/etc/systemd/system/`. Which sequence of commands should the administrator run?

A system administrator notices that a cron job runs every 5 minutes but should run only on weekdays. The current crontab entry is: */5 * * * * /usr/local/bin/script.sh. Which change to the time fields will restrict execution to Monday through Friday?

An AppArmor profile for a web server is in complain mode. After testing, the administrator wants to enforce the profile. Which command accomplishes this?

A database server running on Linux is experiencing high load. The administrator runs 'strace -p <pid>' and sees many 'epoll_wait' and 'futex' calls. Which THREE of the following are possible causes of the high load? (Choose THREE.)

An administrator is troubleshooting a Kubernetes deployment that is not receiving traffic. The deployment has one replica and the pod is running. The service is of type ClusterIP. Which command would help verify that the service endpoints are correctly associated with the pod?

A Linux server becomes unresponsive, and the administrator suspects a process is consuming excessive CPU. The administrator needs to identify the offending process and then terminate it cleanly by PID. Which TWO commands should be used to accomplish these tasks? (Choose two.)

A company needs to verify that the Apache HTTP server is running and see its current status along with recent log entries. Which command should be used?

Based on the exhibit, which statement is true about the sshd service?

A Linux administrator needs to scan all currently connected USB devices and display detailed information such as vendor ID, product ID, and device class. Which command should the administrator run?

A Linux administrator is configuring an SSH server to use certificate-based authentication. The administrator has generated a CA key pair and wants to sign a user's public key. Which command should be used to sign the user's public key with the CA and produce a certificate?

A system administrator is configuring a firewall using iptables. The requirement is to allow incoming SSH connections from the 192.168.1.0/24 network only. Which iptables rule should be added to the INPUT chain?

A Linux administrator writes a bash script that needs to exit immediately if any command fails. Which of the following should be included at the beginning of the script?

A Linux administrator writes a Python script to parse configuration files. Which TWO practices improve security and portability? (Select TWO.)

A Linux administrator is writing a Bash script that must continue running even if an unset variable is referenced, but must still abort on a failed command. Currently the script has only `#!/bin/bash` at the top. Which line should be added to meet these requirements?

A system administrator wants to collect network performance statistics over time, including packet loss and latency, to diagnose intermittent connectivity issues. Which tool combines the functionality of ping and traceroute into a single continuous monitoring command?

A Linux administrator is writing a Bash script that processes a list of hostnames stored one per line in /etc/app/hosts.list. The script must read each line into the variable host and run a command against it, and the loop must not consume standard input from the terminal so that interactive commands inside the loop can still read from the keyboard. Which construct satisfies these requirements?

After a kernel update, the system boots but the network interface enp0s3 is not detected. The administrator verifies that the kernel module for the NIC is built for the new kernel. Which of the following should be done to ensure the module loads correctly?

Which command displays the amount of disk space used and available on mounted filesystems in a human-readable format (e.g., GB, MB)?

Which TWO commands display disk usage information for filesystems? (Select 2.)

A Linux server that hosts a critical database application has been experiencing occasional kernel panics. The administrator wants to ensure the system automatically reboots after a panic and logs the crash dump. Which sysctl parameter should be set?

A Linux administrator notices that a server's root filesystem is filling up rapidly. After running `df -h`, the root filesystem shows 100% usage. However, when the administrator runs `du -sh /*` from the root directory, the total size is only about 40% of the filesystem. The administrator suspects that a deleted file is still being held open by a process. Which command should the administrator use to identify the process holding the deleted file?

A user cannot delete a file owned by another user on a shared filesystem. The file's permissions are 644, and the directory has permissions 777 with the sticky bit set. Which action would allow the user to delete the file?

A system administrator needs to change the hostname of a Linux server running systemd to 'webserver01'. Which command will accomplish this?

A DevOps engineer needs to debug a bash script that unexpectedly fails when processing files. Which of the following should be added to the script to print each command before execution?

A security administrator is reviewing SSH configuration. Which TWO settings enhance security by limiting authentication attempts and preventing password-based logins? (Choose two.)

A system administrator notices that a service named 'myapp' fails to start on a Linux server. The command 'systemctl status myapp' shows 'Active: failed (Result: exit-code)'. Which of the following is the BEST first step to diagnose the issue?

A Linux administrator wants to ensure a Bash script exits immediately if any command fails. Which directive should be included at the beginning of the script?

A developer wants to grant a user named 'john' read and write permissions to a file, but the file currently has an ACL that gives 'jane' full control. The administrator wants to add an ACL entry for 'john' without modifying existing entries. Which command accomplishes this?

A Linux administrator needs to configure a firewall to allow incoming SSH connections only from the 192.168.1.0/24 subnet. The current iptables INPUT policy is ACCEPT. Which set of rules should be added?

A configuration-management script must take a YAML inventory file and convert it into JSON so a downstream API can consume it, preserving all nested structure. Which command accomplishes this most directly?

After a security audit, it is recommended to disable SSH password authentication in favor of key-based authentication. Which configuration line should be set in /etc/ssh/sshd_config?

An administrator wants to capture network traffic on interface eth0, writing the output to a file for later analysis, without resolving hostnames. Which command accomplishes this?

A user reports that an application fails with 'Permission denied' when writing to /srv/reports, even though the user is a member of the group that owns the directory. Running `ls -ld /srv/reports` returns 'drwxr-x--- 2 root reports 4096 Jun 10 09:14 /srv/reports'. The user's `id` output confirms membership in the reports group. Which action will allow the user to create files in that directory?

A security team wants to restrict SSH access to only users in the 'sshusers' group. Which configuration line in /etc/ssh/sshd_config achieves this?

Refer to the exhibit. A server administrator wants to ensure that when a user logs out, all processes started by that user are terminated. Which line should be added to the configuration?

A technician notices a script fails to execute because the user does not have permission. The script currently has permissions 644. The technician needs to add execute permission for the owner only. Which command accomplishes this?

A Linux administrator is troubleshooting intermittent application failures on a server. They suspect resource exhaustion. Which TWO commands can be used to check current system resource limits and usage for a running process? (Choose two.)

A containerized application writes logs to /var/log/app.log. The administrator wants to ensure logs persist even if the container is removed. Which approach should be used?

A Linux administrator is writing a Bash script that must run a cleanup routine when the script exits, whether it exits normally or is interrupted by a signal. The script defines a function named cleanup. Which command should the administrator use to ensure cleanup runs on exit?

A DevOps engineer is writing a Bash script that checks if a file exists and is readable. Which test condition should be used inside an if statement?

A security team wants to harden a Linux server against unauthorized access. They need to restrict which users can authenticate via SSH and ensure that only key-based authentication is allowed for a specific group. Which TWO actions should the administrator take? (Choose two.)

Which THREE of the following are commonly used configuration management and automation tools in the Linux ecosystem? (Choose THREE.)

A Linux administrator is troubleshooting a server that has become unresponsive. They suspect a process is consuming excessive CPU. Which command should they use to display a real-time, interactive view of processes sorted by CPU usage?

A process with PID 2345 is not responding. The administrator wants to force stop the process immediately. Which command should be used?

A technician needs to search a log file for lines containing either 'ERROR' or 'FATAL' and display the line numbers. Which command accomplishes this?

A company runs a critical web application on a single Linux server. The application consists of a Node.js backend and a PostgreSQL database. The server is running out of disk space frequently due to application logs. The administrator wants to implement a log rotation solution that is automated, minimizes data loss, and compresses old logs. The administrator has root access and wants to use built-in tools. Currently, logs are written to /var/log/app/access.log and /var/log/app/error.log. The application never closes its log files. Which of the following is the best course of action?

A Linux administrator wants to prevent users from reusing their last five passwords. Which PAM module should be configured?

A Linux administrator is writing a Bash script that uses a function. Which two statements about Bash functions are correct? (Choose TWO.)

A user reports that they cannot reach a website. The administrator wants to check the path that packets take to the destination server. Which command should be used?

A system administrator needs to monitor system performance over time. Which THREE tools can be used to collect and display CPU, memory, and I/O statistics? (Choose three.)

A Linux administrator receives reports that a web application hosted on the company's internal server is intermittently slow. The server runs CentOS 7 and hosts multiple virtual hosts. The administrator checks system resources and notices that the system's swap usage is high. Which of the following is the MOST likely cause of the performance issue?

In a Kubernetes cluster, a developer needs to create a Deployment that runs three replicas of a container image 'myapp:1.0' and exposes port 8080. Which YAML snippet correctly defines this Deployment?

A user reports that they cannot log in to a Linux server via SSH. The administrator checks /etc/passwd and sees the user's shell is set to /sbin/nologin. What is the most likely reason for the login failure?

A Kubernetes YAML manifest defines a Deployment. Which field specifies the number of pod replicas to run?

A Linux server running RHEL 9 has SELinux in enforcing mode. A web application (Apache) is serving content from a custom directory /var/www/html/myapp. The application needs to write to a subdirectory /var/www/html/myapp/uploads. The administrator sets the context of the uploads directory to httpd_sys_content_t and also runs `restorecon -Rv /var/www/html/myapp`. However, Apache still cannot write to the uploads directory. The administrator checks the SELinux denials in /var/log/audit/audit.log and sees AVC denials related to writing. Which step should the administrator take next?

Drag and drop the steps to create and apply a systemd service unit in the correct order.

A script named 'test.sh' contains '#!/bin/bash' and is located in the current directory. Which command runs the script in the current shell environment without forking a subshell?

An administrator is investigating a system that may have been compromised. The 'aide' database was created six months ago. After running 'aide --check', many files in /usr/bin are reported as changed. Which action should the administrator take first to identify the cause?

A system administrator wants to deploy a containerized application on a Linux server with minimal overhead and without a daemon. Which container runtime should be used?

A junior administrator needs to check whether a user account named 'bob' is locked and view the password aging information. Which command should be used?

A Linux administrator is configuring sudo for a team of developers. The developers need to run commands as the user 'webadmin' without being prompted for a password, but only for commands located in /usr/local/bin. Which sudoers entry correctly implements this?

An administrator is troubleshooting a service that fails to start with a 'Permission denied' error. The administrator runs `strace -f -o /tmp/strace.log systemctl start myservice`. Which of the following best describes what this command achieves?

An administrator runs 'mount -a' and receives the error shown in the exhibit. The /home partition was recently removed and replaced with a new disk. Which of the following steps should the administrator take to resolve the issue?

A user runs a command and receives the error 'bash: myapp: command not found'. The administrator confirms the binary exists in /usr/local/bin. Which environment variable should be checked?

A cron job runs a script that fails because the command 'myapp' is not found. The script works when run manually by the same user. What is the most likely cause?

A Linux server experiences intermittent network connectivity issues. The administrator suspects a duplex mismatch. Which tool can best confirm duplex and speed settings on a network interface?

An administrator notices that a web application intermittently returns 'Connection timed out' to clients on the same subnet, while the server itself responds to pings. Packet captures show the server receiving SYN packets but never replying. The host firewall is suspected. Which command should the administrator use to inspect the active ruleset and its counters on a system using nftables?

A system administrator notices that the /var partition is full, causing log services to malfunction. Which command should be used to quickly reclaim space by removing compressed old log files?

A Linux system experiences high CPU usage from a process that appears to be a fork bomb. The administrator wants to prevent such attacks in the future by limiting the number of processes a user can create. Which configuration file should be modified, and what parameter should be set?

A team wants a shared directory /srv/project where members of the group devteam can create and edit files, but files created by one member must remain editable by other members. The directory is on an ext4 filesystem, and the team does not want to manually change group ownership on every new file. Which command set achieves this?

An administrator wants to monitor real-time system resource usage to identify performance bottlenecks. Which two commands are suitable? (Choose two.)

After using 'apt-get install' to install several packages, the administrator notices that disk space is low. Which command cleans up the package cache?

After configuring AppArmor, an administrator wants to verify the status of all profiles and switch a profile from complain to enforce mode. Which TWO commands are appropriate? (Choose two.)

In a Bash script, what is the purpose of the shebang '#!/bin/bash'?

A user wants to create a hard link named 'linkfile' to an existing file 'original'. Which command accomplishes this?

Match each SELinux context component to its description.

A security audit reveals that users can change their password without meeting complexity requirements. Which PAM module should be configured to enforce password complexity?

A security analyst wants to ensure that users cannot change their password more than once every 7 days. Which command and option should be used to enforce this policy for user 'jsmith'?

A Linux administrator is configuring a server that must meet strict security guidelines. The server uses firewalld and should drop all incoming traffic on the public zone by default, but allow outgoing SSH connections initiated by the server itself to a remote management host. Which firewalld configuration should the administrator apply?

A system administrator notices that a critical application's process is consuming too much CPU, affecting other services. The administrator needs to reduce the CPU priority of that process without affecting its memory or other resources. The process PID is 4521. Which command should the administrator use?

A system administrator wants to schedule a script to run every Monday at 3 AM. Which cron entry is correct?

A Linux administrator needs to run a Docker container in detached mode with port mapping from host port 8080 to container port 80, and mount a host directory /data to /app/data inside the container. Which command achieves this?

Refer to the exhibit. A user reports that they cannot write to /data, receiving a 'No space left on device' error. However, the df output shows 5.2G available. What is the most likely cause?

A system administrator needs to create a new user account with a home directory and the bash shell. Which command should be used?

A technician needs to trace the system calls made by a running process to debug a performance issue. Which tool should be used?

During a security audit, a Linux administrator finds that an unauthorized service is listening on TCP port 4444. The service is not managed by systemd. Which of the following commands should the administrator use to identify the process and disable it?

A system administrator needs to ensure that the Apache HTTP server starts automatically at boot and is started immediately without rebooting. Which command accomplishes both tasks?

A technician notices that a user can execute a binary with elevated privileges even though the user is not in the sudoers file. The binary has the SUID bit set. Which command would remove the SUID bit from the binary?

An administrator needs to replace all occurrences of 'oldhost' with 'newhost' in the file /etc/hosts. Which sed command should be used?

A technician wants to find all files owned by user 'jane' in the /home directory. Which command accomplishes this?

A system administrator is troubleshooting a network issue where a server cannot reach the internet. The server's IP address is 192.168.1.10/24, and the default gateway is 192.168.1.1. Which command should be used to verify the default gateway configuration?

A Linux administrator receives reports that a server becomes unresponsive for several seconds at a time. Running `uptime` shows a load average of 14.2 on a system with 4 CPU cores, and `vmstat 1` reports a steadily rising 'r' column with a 'wa' column near zero. Which command should the administrator run NEXT to identify which processes are consuming CPU time?

In a Bash script, what is the correct way to check if a file named '/etc/passwd' exists and is a regular file?

A Linux administrator is troubleshooting a systemd service that fails to start with the error 'Failed to start myservice.service: Unit myservice.service not found.' The service file exists at /etc/systemd/system/myservice.service and has correct permissions. Which command should the administrator run to resolve the issue?

Which command would a Linux administrator use to locate all files in the /var/log directory that have been modified within the last 7 days?

A Linux administrator is writing a Bash script that processes a list of filenames stored one per line in a file. Some filenames contain spaces. The administrator wants the loop to treat each full line as a single item without word-splitting, and also wants to strip the trailing newline from each item. Which construct accomplishes this?

An administrator wants to force a password change for user 'alice' on next login. Which command is appropriate?

What does the `set -x` command do when placed at the top of a bash script?

You are a Linux system administrator for a small company. You have written a BASH script that checks disk usage and sends an email alert if any partition exceeds 90% usage. The script works when run manually but does not produce alerts when run via cron. Which of the following is the most likely cause?

A Linux administrator needs to grant the user 'alice' the ability to run all commands as root without being prompted for a password, but only from the host 'server1'. Which entry in /etc/sudoers accomplishes this?

An administrator needs to monitor a service's log output and wants systemd to capture the output of a specific service unit into the journal, tagged so it can be filtered by the unit name. The administrator also wants to limit how much disk space the journal may consume so it does not fill the root filesystem. Which configuration accomplishes both goals?

A Linux administrator needs to verify which network interfaces are up and their IP addresses on a server. Which command provides this information?

The script in the exhibit runs successfully but the administrator expects it to indicate success. What change should be made?

An administrator needs to run a container using a specific user ID to match host file permissions. Which Docker option should be used when running the container?

A Linux administrator is writing a Bash script that accepts a filename as its first argument. The script should print an error and exit if the argument is missing. Which construct should the administrator use to reference the first positional parameter and test whether it is empty?

An administrator needs to set up a new LVM volume. Which two commands are necessary in the initial setup before creating a logical volume?

To limit the number of processes a user can create, which file should be configured?

A Linux administrator wants to allow the web server (httpd) to bind to a non-standard port, TCP 8080, without disabling SELinux. The system is running SELinux in enforcing mode. Which command should the administrator run to permanently allow httpd to listen on TCP port 8080?

A security engineer must ensure that a new SSH host key is generated using the Ed25519 algorithm and stored in the default location. Which command accomplishes this?

A Linux administrator is tasked with adding a new 1TB hard drive to a server. The drive has been partitioned and formatted with ext4, resulting in the device /dev/sdb1. The administrator needs the drive to be mounted persistently at /data. After adding an entry to /etc/fstab, the administrator runs 'mount -a' and sees the error: 'mount: /data: mount point does not exist.' Which of the following should the administrator do first to resolve the issue?

An administrator wants to schedule a script to run every Monday at 3 AM. Which crontab entry is correct?

A systems administrator needs to restrict SSH access to a Linux server so that only users in the 'sshusers' group can log in. Which configuration change should be made in /etc/ssh/sshd_config?

After a system update, a server takes significantly longer to boot. The administrator wants to identify which systemd service is causing the delay. Which command provides a detailed analysis of boot time spent by each service?

A system administrator needs to configure sudo so that members of the 'wheel' group can execute any command without a password. Which line should be added to /etc/sudoers (using visudo)?

A developer wants to run a containerized application using Podman in a rootless environment. Which of the following is a key difference between Podman and Docker that the developer should be aware of?

A security audit reveals that an SELinux boolean 'httpd_can_network_connect' is currently off, but a web application requires Apache to connect to a database server. Which command should the administrator use to enable this boolean persistently?

A system administrator is troubleshooting a DNS resolution issue. The command `dig example.com` returns a response, but `ping example.com` fails with 'ping: example.com: Name or service not known'. Which of the following is the most likely cause?

A user reports that a web server is unreachable. The administrator runs 'curl -I https://example.com' and gets no response. Which command should be used next to check if the server is reachable at the network level?

Which command can be used to generate an SSH key pair for user authentication?

A technician needs to check which package provides the file /usr/bin/foo on a CentOS 8 system. Which command should be used?

A user reports being unable to log in because the password is locked. The administrator needs to unlock the account. Which command should be used?

A security policy mandates that user 'alice' must change her password every 60 days and must be warned 7 days before expiration. Which command should be used to enforce this?

A Linux administrator is troubleshooting a service that fails to start. Which THREE files or commands should be checked to diagnose the issue? (Select THREE.)

Which command would display the disk usage of each file and directory in /home in a human-readable format, but only showing one level deep?

A Linux administrator needs to view the contents of a compressed log file without decompressing it. Which command should be used?

A Linux administrator is writing a systemd service unit file. Which three of the following directives are valid in the [Service] section? (Select THREE.)

A Linux administrator receives reports that a server's root filesystem is completely full. They run `df -h` and see that the root partition is at 100% usage. Which command should they use NEXT to identify which directories are consuming the most space?

Which command displays the current default umask value for a user?

Match each Linux runlevel to its standard systemd target.

A Linux administrator is troubleshooting a server that cannot resolve hostnames. The administrator suspects a misconfiguration in the DNS resolver. Which file should be checked first to verify the DNS server addresses?

A security policy requires that user home directories have permissions set so that only the owner has access. A new user 'john' has a home directory with permissions 755. Which command should the administrator run to enforce the policy?

A Linux administrator is hardening a server that runs a custom application. The security team requires that the system enforce password complexity and account lockout policies. The administrator decides to use PAM. Which TWO modules should be added to the appropriate PAM configuration files to enforce these requirements? (Choose two.)

A Linux administrator notices that the /home directory is running low on space. They need to identify which user directories are consuming the most disk space. Which command will display the total disk usage of each immediate subdirectory under /home, in human-readable format, sorted by size?

A Linux administrator needs to configure a system to automatically mount an NFS share at /mnt/data during boot. The NFS server is 192.168.1.100 exporting /export/data. Which file should the administrator edit to add the appropriate entry?

A technician needs to troubleshoot a system that is not booting. Which of the following is the most appropriate first step when using a rescue environment?

Which directory in the Filesystem Hierarchy Standard (FHS) contains variable data such as logs and spool files?

A Linux administrator needs to schedule a maintenance script to run every Monday at 03:15 on a systemd-based server. The script must persist across reboots and must not depend on a user being logged in. Which of the following is the BEST approach?

A Linux administrator is configuring a new server and needs to ensure that the SSH service starts automatically at boot and that the firewall allows SSH connections. The system uses systemd and firewalld. Which two commands should the administrator run? (Choose two.)

Which THREE are best practices for securing a Linux server? (Choose exactly three.)

An administrator needs to permanently mount an ext4 filesystem on /dev/sdb1 to the /data directory. Which file must be edited to ensure the mount persists across reboots?

An administrator wants to use Ansible to ensure that the `httpd` package is installed on all managed nodes. Which Ansible module should be used?

A container started with the above Compose configuration fails to set the system time (clock_settime syscall). Which additional capability is required?

A Linux server has a logical volume that is running out of space. The administrator extends the underlying volume group by adding a new physical volume, then extends the logical volume and resizes the filesystem. Which command should be used to resize the ext4 filesystem after extending the logical volume?

A Linux administrator needs to schedule a script to run every Monday at 3:00 AM. The script is located at /opt/scripts/weekly_report.sh. Which entry should be added to the crontab to accomplish this?

A system administrator notices that a process with PID 1234 is consuming excessive CPU. The administrator wants to terminate this process gracefully. Which command should be used?

A system administrator is troubleshooting why a user cannot execute a script in their home directory. Which TWO conditions could prevent execution? (Choose two.)

A Linux administrator needs to schedule a recurring backup script to run every Monday at 02:30 using the system-wide cron facility on a systemd-based distribution. Which entry correctly achieves this when placed in /etc/cron.d/backup?

A Linux administrator needs to change the permissions of a file to allow the owner to read and write, the group to read only, and others to have no access. Which chmod command should be used?

Which of the following correctly describes the purpose of the /etc/shadow file?

A junior administrator is asked to automate the backup of a configuration file every night at 11 PM. The script /usr/local/bin/backup.sh already exists. Which command should the administrator run to schedule this task?

A Linux administrator notices that a server's root filesystem is using 100% of its inodes, even though `df -h` shows only 60% of the disk space used. Users are unable to create new files. Which command most directly helps identify directories containing large numbers of small files that are consuming inodes?

A user is able to ping the Linux server but cannot connect via SSH. The SSH service is running and listening. Which configuration file should the administrator review FIRST?

A Linux server is configured to allow SSH access for remote administration. The security team wants to limit SSH access to only users in the 'ssh-users' group. Which configuration should be added to /etc/ssh/sshd_config?

A Linux administrator is writing a script that must wait for a background process to finish before continuing. The process ID is stored in a variable. Which command should be used to wait for this process?

An administrator wants to enforce an account lockout policy after five failed login attempts on a Linux system. Which PAM module should be added to the authentication stack?

Which command displays the amount of free and used disk space on all mounted file systems in a human-readable format?

In a Bash script, the administrator wants to capture the output of a command into a variable. Which syntax should be used?

A system administrator configures PAM to enforce account lockout after 3 failed login attempts. Which PAM module should be used?

A security engineer needs to verify the authenticity of a downloaded file using its detached GPG signature (file.sig). Which command should be used?

Which command displays the number of lines, words, and characters in a file?

During boot, a Linux system displays a kernel panic indicating 'not syncing: VFS: Unable to mount root fs on unknown-block(0,0)'. Which of the following is the most likely cause?

A Linux administrator is automating container builds and needs to reduce image size and ensure reproducibility. Which TWO practices should be applied when writing the Dockerfile? (Choose two.)

A user reports that a custom application service fails to start with a 'Permission denied' error in the logs. The service runs under the 'appuser' account. Which is the most likely cause and the first step to diagnose?

A user reports that a recently installed application fails to start. The application was installed via a shell script that added a repository and installed the package. The user runs 'ldd /usr/bin/app' and sees several 'not found' libraries. Which of the following is the MOST likely cause?

A system administrator needs to restrict SSH access to a Linux server to only users in the 'sshusers' group. Which configuration change achieves this?

A security policy requires that all users must have passwords with at least one uppercase letter, one digit, and a minimum length of 12 characters. Which PAM configuration file and module should be used to enforce this?

A Linux administrator needs to find large log files that may be consuming disk space. Which command should be used to locate files larger than 100MB in the /var/log directory?

A Linux administrator needs to add a new user named 'jdoe' with a home directory and default shell /bin/bash. Which command should be used?

An administrator needs to add a script to be executed daily. The script is placed at /etc/cron.daily/myscript. After placing the script, it does not run. Based on the exhibit, what is the most likely issue?

A Linux server is experiencing intermittent network connectivity issues. The administrator needs to capture and analyze network traffic to diagnose the problem. Which TWO commands or tools can be used to capture packets on the eth0 interface? (Choose two.)

A user wants to change the permissions of a file to give the owner full control, the group read and execute, and others no access. Which of the following chmod commands will achieve this?

A Linux administrator is troubleshooting a system that becomes unresponsive under heavy load. They suspect that a process is causing excessive disk I/O. Which command should the administrator use to identify the process performing the most disk writes in real time?

An administrator is investigating a network issue where a server cannot connect to an external website. They run `ping 8.8.8.8` successfully, but `ping google.com` fails. Which TWO of the following are the most likely causes? (Choose TWO.)

A security administrator is hardening a Linux server and wants to verify that the SSH daemon is configured to disallow direct root logins. The administrator has already edited /etc/ssh/sshd_config and set PermitRootLogin no. Which command should the administrator run to ensure the SSH daemon reloads the configuration without terminating existing SSH sessions?

Refer to the exhibit. The service fails to start with the error 'Failed to start My Service: Unit not found'. What is the most likely cause?

A junior administrator needs to change the ownership of the file /var/www/html/index.html from user 'www-data' to user 'apache' and group 'apache'. Which command will accomplish this?

A Linux administrator is troubleshooting a server that is unresponsive. They suspect a process is consuming excessive CPU. Which TWO commands can be used to identify the process with the highest CPU usage? (Choose two.)

A server is experiencing high CPU load. The administrator needs to identify which process is consuming the most CPU resources in real time. Which command should be used?

A Linux administrator is troubleshooting a service that fails to start. The service unit file is located at /etc/systemd/system/myservice.service. The administrator runs 'systemctl status myservice' and sees 'Active: failed (Result: exit-code)'. Which of the following commands will provide the most detailed information about why the service failed?

A user reports that they cannot access a file because permission is denied. The file's permissions are -rwsr-xr-x. What special permission is set?

An administrator needs to capture network traffic on interface eth0, filter for packets to/from host 10.0.0.1, and save the output to a file for later analysis. Which command should be used?

An Apache web server (httpd) is serving content from a custom directory /webapps/company. The root directory is labeled with the default_t context, causing httpd to be denied access. Which command should the administrator use to persistently relabel the directory for httpd access?

Which of the following commands will display the last 10 lines of a log file and also output new lines as they are appended?

A system administrator runs 'umask 027' in a Bash shell. What will be the default permissions for a new directory created in that shell? (Assume no other umask changes.)

A Linux administrator discovers that a user's home directory contains a file with setuid bit set, owned by root. The file is not part of any authorized software. What is the most appropriate immediate action?

An administrator notices that a process is running with the context 'unconfined_u:unconfined_r:unconfined_t:s0'. What does this indicate about SELinux?

In a Bash script, what is the difference between single quotes and double quotes?

A DevOps engineer is creating a Dockerfile for a Node.js application. Which THREE of the following instructions are valid and commonly used in a Dockerfile? (Choose THREE.)

An administrator wants to verify which RPM packages are installed on a Red Hat Enterprise Linux system. Which command displays that information?

A developer reports that a Docker container on a CentOS 7 host cannot connect to the internet. The host itself can access the internet. The container is started with default bridge network. The administrator checks iptables and sees the FORWARD policy is DROP. What is the most likely cause and solution?

A Linux administrator needs to check which services are listening on TCP ports on a server. Which command should be used to replace the deprecated netstat command?

Which TWO statements are true regarding the use of Ansible for automation? (Choose TWO.)

Based on the exhibit, what best describes the security implication?

Drag and drop the steps to configure a static IP address using the command line in the correct order.

A Linux administrator is troubleshooting a systemd service that fails to start. The service unit file is located at /etc/systemd/system/myservice.service. After editing the unit file, the administrator runs systemctl start myservice, but the service still uses the old configuration. Which command should be run to ensure systemd reloads the modified unit file?

A system administrator is hardening SSH and needs to disable root login and password authentication. Which two directives should be set in /etc/ssh/sshd_config?

An administrator wants to generate a self-signed certificate and private key for testing. Which command creates both in one step?

A system administrator needs to add an iptables rule to drop incoming TCP traffic on port 22 (SSH) from the IP address 10.0.0.100. Which command should be used?

Which TWO conditions must be met for a user to successfully delete a file owned by a different user in a directory? (Choose two.)

A Linux administrator is hardening a server. Which TWO actions are effective in preventing unauthorized access via SSH? (Select TWO.)

A system administrator is investigating a performance issue and wants to view kernel-related messages. Which three commands can be used to access kernel ring buffer messages? (Choose three.)

A Docker container needs to persistently store data that should survive container removal and be accessible by other containers. Which storage method should be used?

An administrator needs to trace system calls made by a process that is misbehaving. Which command should be used to attach to the running process and display its system calls?

During the boot process, after the kernel is loaded and the initramfs is executed, which component is responsible for starting the user-space services and managing the system state?

A sysadmin wants to run a containerized web application using Podman. The container needs to persist data across restarts. Which approach ensures data persistence?

A Linux administrator is troubleshooting a service that fails to start. The audit.log shows an AVC denial related to the httpd_t domain. The administrator wants to see the full denial message and generate a policy to allow the access. Which two commands should be used in conjunction?

An administrator wants to run a script every Monday at 3:00 PM using a systemd timer. Which unit file configuration is correct for the timer?

An administrator notices that an AppArmor profile is in complain mode for a service that should be enforcing. Which command changes the profile to enforce mode?

An administrator is troubleshooting an AppArmor profile that is blocking a custom application. They want to set the profile to complain mode to gather violations without enforcing. Which command should they use?

An administrator notices that the /var partition on a production server is nearly full and wants to determine which subdirectories consume the most space before deleting anything. The administrator has root privileges and wants a human-readable summary of each immediate subdirectory under /var, one line per directory. Which command accomplishes this?

An automation engineer uses Ansible to configure a fleet of Linux servers. A playbook task installs a package and then starts a service, but the service fails to start because the package installs a configuration file only on the first run. The engineer wants the handler to notify only when the package actually changes state. Which Ansible construct ensures the service restart handler fires only when the package task reports a change?

A security audit has identified that several users have excessive sudo privileges. The administrator needs to review and modify sudo access. Which two files or commands would be used? (Choose TWO.)

An administrator wants to check the amount of free memory and swap usage on a system in a human-readable format. Which command should be used?

A system is experiencing high CPU usage due to a background process with PID 2345. The administrator wants to reduce the process's priority by 5 without stopping it. Which command should be used?

An administrator runs the commands shown in the exhibit. The container is accessible via curl using the container IP. However, the administrator cannot access the web server using the host's IP address on port 80. What is the most likely cause?

An administrator needs to set a password expiration policy so that all users must change their password every 90 days. Which command and option accomplishes this for an existing user?

An administrator needs to identify which processes are consuming the most CPU and memory resources. Which two commands can provide this information? (Choose two.)

An administrator needs to find all files in /var/log that have been modified within the last 2 days. Which find command should be used?

A Linux administrator needs to automate the deployment of a Kubernetes application from a manifest file and verify that the rollout completes successfully within a script. Which pair of actions should the script perform to apply the manifest and block until the Deployment's rollout finishes?

A team uses Ansible for configuration management. They want to ensure a service is running on all managed nodes. Which Ansible module should be used in the playbook?

To harden SSH, an administrator needs to disable root login over SSH. Which directive should be set in /etc/ssh/sshd_config?

A user named 'jdoe' needs to run commands as root without being given the root password. The administrator wants to grant jdoe the ability to run any command as root, but only after entering their own password. Which entry in /etc/sudoers accomplishes this?

After a system update, a custom application no longer runs due to a shared library error. The library exists on the system but is in a non-standard path. Which environment variable should be checked or set to resolve this?

A system administrator is tasked with ensuring that users cannot delete files owned by other users in a shared directory. Which permission should be set on the directory?

Which directory in the FHS contains essential user command binaries that are needed in single-user mode?

A Linux engineer needs to ensure a bash script runs with strict error handling. Which TWO of the following should be included? (Choose two.)

In a bash script, a developer needs to parse command-line options such as -f filename and -v (verbose). Which built-in command is best suited for this task?

An administrator is configuring a server to act as a router and needs to enable IP forwarding persistently across reboots. Which file should be modified?

A security audit reveals that a service is running with an incorrect SELinux context. Which two commands can be used to relabel the file or directory to the correct context? (Choose TWO.)

A system administrator needs to identify which processes are consuming the most memory on a Linux server. Which two commands can be used? (Select TWO).

A junior administrator needs to view the logs of a running container named 'webapp'. Which command should be used?

A user cannot start the Apache web service. The command 'systemctl start httpd' returns 'Failed to start httpd.service: Unit not found.' What is the most likely cause?

Refer to the exhibit. A user cannot access a web server, but another host on the same subnet can. What is the most likely cause?

A security administrator needs to configure a Linux server so that all users must use a password of at least 12 characters and include at least one uppercase letter, one lowercase letter, one digit, and one special character. Which file should be edited to enforce these requirements?

A user reports that they cannot access a website by domain name but can access it by IP address. Which of the following is the most likely cause?

A Linux server is configured to use Pluggable Authentication Modules (PAM). Which file is used to define the authentication order for the 'sshd' service?

Refer to the exhibit. The system administrator runs the command 'auditctl -l' and sees the above rules. What is the purpose of these audit rules?

A Linux administrator needs to prevent the root user from logging in via SSH. Which directive should be set in /etc/ssh/sshd_config to accomplish this?

An administrator needs to check the current routing table on a Linux system. Which command should be used?

A technician is troubleshooting a network connectivity issue. They need to trace the path packets take to a remote server and see the round-trip time for each hop. Which command should they use?

A Linux administrator is troubleshooting a Bash script that must parse each line of a file named `servers.txt` and process fields separated by colons. The script currently uses `for line in $(cat servers.txt)` and breaks on lines containing spaces. Which construct should replace the loop to correctly iterate over lines while preserving whitespace?

A server is unable to resolve hostnames via DNS. The /etc/resolv.conf file appears correct. Which command can be used to test DNS resolution and display the full query path?

A junior administrator runs `sudo useradd -m -s /bin/bash devops` on an Ubuntu 24.04 server, then immediately tries to SSH in as devops using a key that was copied to /home/devops/.ssh/authorized_keys. The login fails with 'Permission denied (publickey)'. The sshd_config has PubkeyAuthentication yes and PasswordAuthentication no. Which command is the most appropriate next step to resolve the login failure while preserving the intended account setup?

A Linux administrator is automating container lifecycle tasks with a script and needs to ensure a specific container, named webapp, is stopped cleanly and removed, while also removing its anonymous volumes. Which TWO docker commands should be used to accomplish this? (Choose two.)

A web server running on port 8080 must be accessible from external networks. The system uses firewalld. Which command opens port 8080/tcp permanently in the default zone?

A Linux server in a DMZ is experiencing intermittent SSH lockouts. The /var/log/secure shows repeated failed login attempts from multiple IP addresses, but then suddenly the administrator cannot SSH in even with correct credentials. The administrator suspects a brute-force protection mechanism. The server uses PAM with pam_tally2 for login counting. The administrator checks /etc/pam.d/sshd and sees: auth required pam_tally2.so deny=3 unlock_time=300 onerr=succeed file=/var/log/tallylog. What is the most likely reason the administrator is locked out even after 5 minutes?

A system administrator is troubleshooting a network issue on a Linux server running CentOS 7. The server is unable to connect to the internet, but internal network connections work fine. The administrator checks the network configuration: the server has a static IP 192.168.1.100/24, default gateway 192.168.1.1, and DNS server 8.8.8.8. The administrator can ping the gateway but cannot ping 8.8.8.8. From the server, a traceroute to 8.8.8.8 stops at the gateway. The administrator also notices that the route table shows a default route via 192.168.1.1. What is the most likely cause?

A user cannot access a website, but other websites work. The administrator wants to see the HTTP response headers from the web server. Which command is most appropriate?

A Linux administrator needs to identify which of the following filesystems are journaling filesystems commonly used in Linux. (Choose three.)

Which command will create a compressed tar archive of a directory?

A Linux administrator needs to ensure that a custom application service, implemented as a oneshot systemd unit, runs only after the network is fully online and the /data filesystem is mounted. The unit file currently has no ordering directives. Which systemd directive should be added to the [Unit] section to define these ordering dependencies?

A user reports that they are unable to write to a USB drive mounted at /mnt/usb. The administrator checks the mount options and sees that the drive is mounted read-only. Which command should the administrator use to remount the filesystem as read-write without unmounting it?

After updating the kernel, the system fails to boot and displays 'Error 15: File not found' from GRUB. What is the most likely cause?

A Linux administrator writes a Bash script that processes a list of hostnames read from a file and must continue processing remaining hosts even if an SSH command to one host fails. The script currently uses set -e and exits on the first failure. Which change allows the loop to keep running while still exiting on other unhandled errors?

A Linux server has SELinux enabled. An administrator wants to temporarily set the SELinux mode to permissive without rebooting, then confirm the change. Which command should be used?

A Linux administrator is writing a bash script that must exit immediately if any command fails. Which of the following should be included at the beginning of the script?

Which of the following directories is defined by the Filesystem Hierarchy Standard (FHS) as containing essential user command binaries that need to be available in single-user mode?

A Linux administrator is troubleshooting a system that is running out of disk space on the root filesystem. The administrator needs to identify which directories are consuming the most space. Which TWO commands can be used to find the largest directories? (Choose two.)

A Linux administrator needs to ensure that user passwords meet a minimum length requirement of 12 characters. The system uses PAM and the pam_pwquality module. Which file should the administrator edit to set the minlen parameter?

A system administrator notices that a Linux server is running low on disk space. Which command should be used to identify which directories are consuming the most space?

A technician needs to ensure a service can listen on TCP port 8443 using firewalld. Which command permanently adds the port to the default zone?

A web server in a remote data center logs timestamps in UTC, but the operations team wants all logs to reflect the local timezone (America/New_York). Which command changes the system timezone?

A system administrator wants to find all files in /var/log that have been modified in the last 7 days and are larger than 100MB. Which command should be used?

An administrator is managing a server using systemd and needs to control services and units. Which THREE of the following are valid systemd commands for service management? (Choose three.)

A Linux administrator is troubleshooting a server that intermittently loses network connectivity. They suspect duplicate IP address conflicts on the local subnet. Which TWO commands can be used to detect whether another host is using the same IP address as the server? (Choose two.)

A Bash script contains the following function: ```bash myfunc() { local result="$(( $1 + $2 ))" echo "$result" } ``` If the script calls `myfunc 5 10`, what is the output?

In a bash script, a function is defined to calculate a value. Which TWO of the following are valid ways to return a value from the function to the caller? (Select TWO).

A system administrator notices that a server's disk space is critically low. Which command should be used to identify the largest files or directories consuming space?

A Linux administrator needs a scheduled task to run a backup script at 02:30 every day of the week. The system uses cron, and the administrator is editing the crontab for the `backup` user. Which crontab entry accomplishes this?

A Linux administrator is troubleshooting a server that has lost network connectivity. The administrator runs `ip a` and sees that the interface `ens33` is in the DOWN state and has no IP address assigned. The administrator wants to bring the interface up and assign it an IP address of 192.168.1.50/24. Which command should the administrator use?

An administrator is creating an Ansible playbook to configure multiple web servers. Which of the following are valid ways to define variables for different groups of hosts? (Choose TWO.)

A security team wants to implement mandatory access control (MAC) on a Linux server to confine a potentially vulnerable daemon. Which TWO of the following technologies can be used for this purpose?

Which command can be used to display the current user's effective user ID and group memberships?

A service named 'myapp' is currently running but should be disabled so it does not start automatically at boot. Which command accomplishes this?

A Linux administrator is implementing mandatory access control using AppArmor on an Ubuntu server. A custom web application profile is loaded in enforce mode, but the application is failing to write to /var/log/myapp/. The administrator wants to temporarily switch the profile to complain mode to diagnose the issue without disabling AppArmor entirely. Which command should be used?

Which command is used to query the status of a service managed by systemd?

An administrator runs 'auditctl -w /etc/passwd -p wa -k passwd_changes' to monitor changes to /etc/passwd. Which command should be used to search the audit log for all events related to this watch?

A script receives a JSON object where keys are user IDs. Which command extracts the 'status' of user id '123'?

Which TWO commands can be used to change the group ownership of a file? (Choose exactly two.)

A Linux administrator is using Git to manage a configuration repository. They need to undo a commit that has already been pushed to a shared remote repository, without rewriting history. Which command should they use?

A Linux administrator needs to ensure that a new service, myapp.service, starts automatically at boot and is currently running. The administrator runs 'systemctl enable --now myapp.service' and receives no errors, but after a reboot the service is not running. Which of the following is the most likely cause?

A system administrator is troubleshooting a Docker container that exits immediately after starting. The container is built from a minimal image that runs a short-lived command. Which change will keep the container running?

In an Ansible playbook, which THREE of the following are valid modules for managing files and packages? (Select THREE).

A Linux system is using systemd and a service fails to start. The administrator checks the service journal and sees: 'Failed to start service: Unit not found'. However, the service file exists in /etc/systemd/system/. What is the most likely cause?

A Linux administrator needs to allow members of the group 'developers' to run all commands as root without being prompted for a password, but only from the host 'build01'. The administrator adds the following line to /etc/sudoers: '%developers build01=(ALL) NOPASSWD: ALL'. After saving, users report that sudo still prompts for a password on build01. Which command should the administrator run to verify the syntax and placement of the rule?

A process is consuming excessive CPU and needs to be stopped immediately. The process ID is 4582. Which command should be used?

A Bash script uses getopts to parse command-line options. The script is invoked as: ./script -a -b value. Which getopts string should be used to correctly parse -a (no argument) and -b (requires an argument)?

A Linux administrator writes a Bash script and includes the line `#!/bin/bash` at the top. What is the purpose of this line?

A security administrator is hardening a Linux web server and wants to reduce the attack surface of the SSH service. Which TWO actions should be taken in /etc/ssh/sshd_config to restrict access and authentication? (Choose two.)

An administrator needs to verify DNS resolution for a web server. Which TWO commands can be used to query DNS A records for a given hostname? (Choose two.)

A systems administrator wants to monitor system performance in real time. Which TWO commands can be used to display live updating information about processes, CPU, and memory usage? (Select TWO.)

A server running a critical application needs to be rebooted. To ensure the application stops gracefully and data is not corrupted, which sequence of commands should the administrator use?

A security audit reveals a misconfiguration. Which file has insecure permissions that could allow unauthorized users to read password hashes?

An administrator is building a container image and needs to reduce its final size while keeping the build reproducible. Which TWO practices improve image efficiency and build reliability? (Choose two.)

A Linux administrator needs to permanently set the system-wide umask to 027 for all users on a production server. The administrator edits /etc/profile and adds the line 'umask 027'. After rebooting, a user logs in and runs 'umask', which returns 0022. Which of the following is the most likely reason the setting did not take effect?

A developer is writing a Dockerfile. The application requires a configuration file that should be copied from the build context and the container should expose port 8080. Which combination of Dockerfile instructions is correct?

An administrator wants to ensure a service starts automatically at boot on a systemd-based system. Which command should be used?

A Linux administrator notices that a server's clock is drifting and NTP synchronization is failing. The administrator runs 'chronyc sources' and sees that all sources are marked with a '?' character. Which command should be run next to diagnose why chronyd cannot reach the NTP servers?

A system fails to boot after installing a new SATA disk. The BIOS recognizes the disk. What is the most likely cause?

A Linux administrator needs to create a new user account named 'jsmith' with a home directory /home/jsmith and the default shell /bin/bash. Which command should the administrator use?

An administrator wants to harden SSH access by implementing the following: disallow root login, disable password authentication, and limit the number of authentication attempts. Which three configuration directives should be set in /etc/ssh/sshd_config? (Choose THREE.)

An administrator notices repeated failed login attempts in /var/log/secure. The company policy requires account lockout after 5 failed attempts within 15 minutes. Which PAM module and configuration can enforce this?

In a Bash script, which THREE of the following are valid ways to define a function? (Select THREE.)

A cloud engineer needs to automate the deployment of a new virtual machine with a specific configuration using Ansible. Which file format is typically used for Ansible playbooks?

A user reports that their system is unable to boot after a recent kernel update. The system displays a 'kernel panic' message. Which of the following is the MOST efficient way to boot into a previous kernel version?

An administrator wants to find all files in /var/log that have been modified within the last 2 days and have a .log extension. Which command should be used?

Which command is used to create a symbolic link named 'link' pointing to the file 'original'?

A Linux engineer is troubleshooting a server that fails to boot. The server displays a message indicating 'Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)'. Which TWO actions should the engineer take to resolve this issue? (Choose TWO.)

A system administrator notices that a web server is running but users cannot connect to port 443. Which ss command will show if the server is listening on that port?

Drag and drop the steps to troubleshoot a network connectivity issue using common commands in the correct order.

Based on the exhibit, how often does the healthcheck.sh script run?

A server is experiencing intermittent high load. The administrator suspects a memory leak in a service. Which sysfs file should the administrator monitor to track memory usage per cgroup?

A shared directory requires that any new files created within it are automatically writable by the group. What umask value should be set for users working in this directory?

An administrator wants to grant a specific user, 'jdoe', read and write access to a file that is owned by root:root with permissions 640. The administrator does not want to change the file's owner or group. Which approach should be used?

A system administrator notices that the server is performing poorly. Running 'vmstat 1 5' shows high 'wa' values. Which subsystem is most likely experiencing a bottleneck?

Which TWO characteristics apply to Docker containers compared to virtual machines? (Choose two.)

In a Bash script, a variable is assigned the output of a command using: result=$(ls -l). What is the purpose of the $() syntax?

A systems administrator writes a Bash script named 'backup.sh' and wants it to run with the Bash shell. Which line should appear first in the script?

A technician has just performed system maintenance and wants to verify that the server has been running continuously for the past 30 days. Which command should the technician use?

A Linux server hosts a payroll database. The security policy states that the file /srv/payroll/ledger.db must be readable and writable only by members of the group payroll, and that no other user on the system may read it, even root. Which approach satisfies the requirement that even root cannot read the file contents?

A system administrator needs to update a configuration file on multiple servers using Ansible. The playbook must ensure the line 'MaxAuthTries 3' is present in /etc/ssh/sshd_config. Which Ansible module is most appropriate?

Which command will show the environment variables for a specific process?

A Linux server is not accepting SSH connections. The administrator wants to troubleshoot the issue. Which THREE actions should be taken?

An administrator runs 'systemctl list-units' and sees that httpd.service is in a failed state. To quickly see the error message that caused the failure, which command should be used?

A Linux administrator is troubleshooting a server that has lost network connectivity. They need to verify the current IP configuration and check the default gateway. Which TWO commands can be used to display the IP address and routing table? (Choose two.)

A database server is experiencing slow queries. The administrator wants to analyze system memory usage. Which command shows memory usage in megabytes and includes information about buffers and cache?

A Kubernetes pod has a container that fails with CrashLoopBackOff. The administrator runs 'kubectl logs pod-name' but sees no output. What is the most likely cause?

In a bash script, a variable is set as follows: myvar='Hello World'. Which of the following correctly prints the first 5 characters of the variable?

A Docker container using port 8080 fails to start with the error 'port is already allocated'. Which command should the administrator use to identify the process using that port?

An administrator is debugging a Docker container that exits immediately after starting. Which THREE commands can help diagnose the issue? (Select THREE).

A junior administrator needs to check the disk usage of the /var filesystem to ensure it does not exceed 80% capacity. Which command should be used?

A developer is writing a shell script that needs to handle errors. Which THREE of the following are best practices for robust script error handling?

A Linux administrator is troubleshooting a Bash script that unexpectedly terminates when a command fails. The script uses `#!/bin/bash`. Which of the following commands, if placed at the beginning of the script, would cause it to exit on any command failure?

A developer creates a hard link to a file and then deletes the original file. What happens to the hard link?

A user is unable to resolve hostnames on a Linux system. Which three configuration files should be checked? (Select THREE).

A storage administrator needs to automate the expansion of an LVM volume group when free space drops below 10%. The script must add a new physical volume from a spare disk. Which of the following commands should be used in the script to add the new disk to the volume group?

A Linux administrator needs to schedule a backup script to run every day at 2:30 AM. Which TWO of the following methods can be used to achieve this? (Choose two.)

A user cannot access a directory '/data/projects' even though they are in the 'projects' group. The directory permissions are 'drwxr-x---' and the group owner is 'projects'. Which command should the administrator run to grant the group write permission?

A Linux administrator needs to check the available disk space on all mounted filesystems in a human-readable format. Which command should the administrator use?

A Linux administrator needs to create a new user account 'analyst' with a home directory at /home/analyst and the default shell set to /bin/bash. The user should also be added to the existing supplementary group 'research'. Which command will accomplish this in a single step?

After a kernel update, loading a proprietary kernel module fails with 'Invalid module format'. The module was built from source against the previous kernel. What is the most likely cause?

A Linux administrator notices that the system’s disk I/O performance has degraded significantly. Running 'iostat -x 1' shows high %util values on /dev/sda, but low await. Which of the following is the most likely issue?

A security policy requires that user passwords must expire after 90 days. The output in the exhibit shows the current configuration for the root user. Which command should the administrator run to enforce the policy for root?

A Linux administrator is writing a Bash script that must safely process a list of filenames, some of which may contain spaces or special characters. The script reads each line from a file into a variable and then iterates over the entries. Which TWO practices should the administrator follow to avoid word-splitting and globbing issues? (Choose two.)

A system administrator is investigating a slow website. The web server is responding but pages load slowly. Which THREE commands can help identify network latency or packet loss?

An administrator is troubleshooting a server that is experiencing intermittent high load. The administrator wants to identify processes that are using excessive CPU. Which two of the following commands can provide real-time CPU usage per process? (Choose two.)

A Linux administrator needs to ensure that only the root user can run commands in the /usr/local/bin/scripts directory. Which command should be used to set the appropriate permissions?

During peak hours, a web server experiences timeouts. The kernel log shows 'possible SYN flooding'. Which kernel parameter should be increased to mitigate this?

A Linux administrator is reviewing an Ansible playbook that manages a fleet of servers. The playbook must run a task only on hosts in the group webservers and must notify a handler when a configuration file changes. Which TWO of the following are valid Ansible constructs that the administrator should use? (Choose two.)

A Linux administrator writes a script that uses bash-specific features like arrays and process substitution. Which shebang should be used?

A system administrator wants to automate server configuration and management across multiple Linux hosts. Which TWO tools are configuration management solutions designed for this purpose? (Choose two.)

Users report that a web application on a Linux server is unreachable from external clients. From the server itself, curl http://localhost works fine. The administrator wants to confirm whether the service is bound only to the loopback interface. Which command should the administrator run?

Scenario: A cloud hosting company uses SELinux in enforcing mode on all Linux servers. A developer reports that a custom web application running under Apache (httpd) is unable to write log files to /var/log/myapp/. The directory /var/log/myapp/ has permissions 755 and is owned by root:root. The httpd process runs as the 'apache' user. The administrator checks SELinux context: /var/log/myapp is labeled with default_t type. The administrator wants to allow httpd to write to this directory while maintaining security. Which command should the administrator run?

An administrator needs to check the kernel ring buffer for hardware error messages after a system crash. Which command should be used?

A Linux server is experiencing high CPU usage. Which TWO commands can be used to identify which processes are consuming the most CPU? (Choose two.)

A security audit identifies that the system's /etc/passwd file is world-readable. Which three security issues does this pose? (Select THREE.)

Which command displays the current routing table on a Linux system?

A Linux administrator needs to add a new user named 'jdoe' with a home directory and bash shell. Which command accomplishes this?

An administrator modified kernel parameters in /etc/sysctl.conf. Which command applies the changes without rebooting?

A Linux administrator needs to inspect the capabilities assigned to the /usr/bin/ping binary to verify it can open raw sockets without being setuid root. Which command should be used?

A Linux administrator is troubleshooting a service that fails to start. Which TWO commands can be used to view the last 20 lines of the systemd journal for the sshd unit?

An administrator wants to start a long-running script in the background so that it continues running even after logging out. Which command should be used?

Refer to the exhibit. A user wants to execute the script 'script.sh' but receives a 'Permission denied' error. Which action should be taken to allow execution?

An administrator wants to change the priority of a running process with PID 1234 to a lower priority (nicer). The current nice value is 0. Which command will set the nice value to 10?

A Linux administrator is writing a bash script that accepts command-line options: -a for all, -f for file, and -o for output. Which of the following correctly uses getopts to parse these options?

A DevOps engineer is designing a CI/CD pipeline for a microservices application. The pipeline should build a Docker image, run unit tests, and if successful, push the image to a private registry. Which tool is best suited for orchestrating this pipeline?

Drag and drop the steps to set up a cron job that runs a script daily in the correct order.

A Linux administrator needs to locate all files in the /var directory that have been modified within the last 30 minutes and are larger than 10MB. Which command accomplishes this task?

A server is experiencing intermittent network connectivity issues. The administrator wants to run a continuous test that combines ping and traceroute to monitor the path and packet loss to a target host. Which command should be used?

A Linux administrator needs to locate all files in the /etc directory that have been modified in the last 24 hours and are not owned by root. Which two commands can be combined to achieve this? (Select TWO.)

A server is secured with SELinux in enforcing mode. A custom web application needs to write logs to /var/log/webapp. The SELinux type for httpd is httpd_t. Which command sets the correct context for the log directory?

The company password policy requires minimum length, complexity, and that passwords cannot be based on dictionary words. Which file should be edited to configure these settings via pam_pwquality?

A Linux administrator needs to view all current IPv4 addresses assigned to network interfaces on a system. Which command should be used?

A Linux administrator is debugging a Bash script that uses a function to set a global counter. The function increments the variable, but after the function returns, the counter retains its original value. The script does not use subshells or pipelines around the function call. Which of the following is the MOST likely cause?

A container is running and a technician needs to execute an interactive shell inside it. The container was started with 'docker run -d --name myapp myimage'. Which command will achieve this?

An administrator is hardening SSH and wants to disable root login and only allow users in the 'sshusers' group. Which two directives should be set in /etc/ssh/sshd_config?

A user wants to create a hard link to a file. Which three conditions must be true for a hard link to be created successfully? (Choose three.)

A user reports that they receive 'Permission denied' when trying to run a script located in their home directory. The script has permissions -rw-rw-r-- and is owned by the user. Which command should the user run to resolve the issue?

A user is trying to log in to a Linux server via SSH but receives 'Permission denied (publickey,gssapi-keyex,gssapi-with-mic)'. The user's public key is in ~/.ssh/authorized_keys with proper permissions (600) and owned by the user. The server's sshd_config has 'PubkeyAuthentication yes' and 'PasswordAuthentication no'. What is the most likely additional cause?

A Linux server is experiencing intermittent network connectivity issues. The administrator suspects that the network interface is dropping packets due to a duplex mismatch. Which command should be used to check the duplex setting and link status of the interface?

An administrator is writing a Bash script that must run a cleanup function when the script exits, whether it finishes normally or is interrupted. Which construct guarantees the function runs in both cases?

Which file contains user password hashes and aging information on a Linux system?

A security policy requires that user passwords must be changed every 60 days, and users should be warned 7 days before expiration. Which two chage commands set these requirements for user 'jsmith'? (Choose TWO.)

Which TWO options are valid ways to pass environment variables to a Docker container?

After adding a new static route to a server, an administrator notices that traffic to 10.20.0.0/16 still leaves through the default gateway. The route appears in 'ip route' output but is not used. The administrator confirms the interface is up. Which command should be run to verify that the kernel is selecting the intended route for that destination?

Refer to the exhibit. A user reports that the /var directory is not accessible. The system administrator checks the logical volumes and notices that the 'var' logical volume is not activated. Which command should be used to activate it?

A Linux administrator is writing a Bash automation script that must continue processing the remaining entries in a loop even when an individual command returns a non-zero exit status. The script currently starts with `#!/bin/bash` and uses `set -e` for safety elsewhere. Which construct should the administrator use to run a command whose failure must be tolerated inside the loop?

A storage administrator is troubleshooting high disk I/O latency. Which THREE tools can provide detailed block I/O statistics at the device level? (Choose three.)

Which TWO commands are used to view a file page by page?

Which shebang ensures maximum portability across systems for a Python script?

A system administrator is investigating high disk I/O on a server. Which command can provide disk utilization statistics, including average wait time (await) and percentage of CPU time during which I/O requests were issued (%util)?

A user reports that a specific process is consuming too much CPU. The administrator needs to change the priority of the process to a lower value (nicer). Which command sequence is appropriate?

A Linux administrator is writing a Bash script that must read a file line by line and preserve leading whitespace in each line. The script currently uses `for line in $(cat file.txt)`. Which construct should replace the current loop to preserve whitespace and avoid word splitting?

A junior administrator needs to add a persistent mount entry for a new XFS filesystem on /dev/sdb1 at the /data directory so it is mounted automatically at every boot. The administrator opens /etc/fstab and must identify the correct field order for the entry. Which field order should be used in the /etc/fstab line?

An administrator is configuring a chroot jail for an SFTP user. Which directive in /etc/ssh/sshd_config is used for this purpose?

A Linux administrator needs to configure the system so that all users must use a minimum password length of 12 characters. The administrator edits /etc/security/pwquality.conf. Which line should be added or modified to enforce this requirement?

A Linux administrator needs to view the last 10 lines of a log file named 'syslog'. Which command should be used?

A Linux administrator is writing a systemd unit file at /etc/systemd/system/backup.service that must execute /usr/local/bin/backup.sh only after the network is fully reachable and the /mnt/archive mount is active. The unit currently has no ordering directives. Which directive should be added to the [Unit] section to satisfy this requirement?

A Linux engineer is troubleshooting a boot issue. The system boots to a command-line interface but does not start the graphical interface. Which systemd target should be set as default to boot into a graphical environment?

A server running Ubuntu 22.04 has AppArmor enabled. After installing a new application, the application is denied access to certain files even though the permissions are correct. The administrator checks the AppArmor profile and finds it is in enforce mode. Which command can be used to temporarily set the profile to complain mode to generate log entries for needed accesses?

A Linux administrator needs to schedule a script at /opt/scripts/report.sh to run every Monday at 02:30 for the user svcacct, without editing the system-wide /etc/crontab. Which cron entry correctly accomplishes this when placed in svcacct's crontab via crontab -e?

A Linux administrator wants to search for all occurrences of the word 'ERROR' in log files under /var/log, ignoring case, and also print the line numbers. Which command should be used?

A Linux server has SELinux enforcing and a custom application needs to write to /var/log/app.log. The audit log shows 'avc: denied { write } for pid=1234'. After verifying that the application runs in the correct domain, which command should be used to allow the write access by generating a policy module?

A company policy requires that only the root user can schedule cron jobs. Which configuration ensures this?

Match each Linux networking command to its purpose.

A system is running slowly and the administrator suspects a memory leak. Which THREE commands or tools can be used to analyze memory usage and identify processes consuming excessive memory? (Choose three.)

A system administrator needs to ensure that only specific users can execute the 'sudo' command. Which configuration file should be modified?

A Linux administrator wants to search for the pattern 'ERROR' in all files under /var/log, ignoring case, and display line numbers. Which THREE options should be used with the grep command? (Select THREE).

A DevOps engineer needs to run a Docker container in the background with port mapping from host port 8080 to container port 80, and name the container 'webapp'. Which command accomplishes this?

A script needs to iterate over all .txt files in a directory. Which loop structure correctly implements this?

A user reports that they cannot run the command `sudo` to perform administrative tasks. The administrator checks and finds that the user is not listed in the `/etc/sudoers` file. Which command should the administrator use to safely edit the sudoers file and add the user?

An administrator is troubleshooting a web server that is running under SELinux enforcing mode. The web content is located in a non-standard directory /webfiles. Using the standard SELinux context 'httpd_sys_content_t', the files are still inaccessible. Which command will properly set the context recursively and persist across relabels?

A sysadmin is tasked with creating a script that will run only on weekdays at 9:00 AM using cron. The script should not run on holidays. Which approach best achieves this requirement?

An administrator manages a server with several systemd services. A service named reportgen.service must not start until another service named dbengine.service is fully active, and reportgen should be stopped automatically if dbengine stops. Which directive combination in the reportgen.service unit file achieves this ordering and dependency?

A technician suspects a process is leaking file descriptors. Which command can be used to list open files associated with a specific PID?

A Linux server intermittently loses its default route after several hours of uptime, and users cannot reach external networks until the route is manually restored. The administrator suspects that a second default route is being installed and removed by a network management daemon. Which command should the administrator use to monitor route changes in real time?

A DevOps team wants to automatically run tests before every commit in a local Git repository. Which Git hook should be used?

A cloud engineer is using Ansible to manage configuration across multiple servers. The engineer needs to store variable data that is specific to each host and sensitive database passwords. Which two Ansible features should be used for these purposes? (Choose two.)

A security policy requires that users cannot reuse any of their last 5 passwords. Which PAM module and configuration directive enforces this?

An administrator runs the command `ls -l file.txt` and sees the permissions `-rwsr-xr-x`. What special permission is set on this file?

An administrator needs to ensure that a script runs once at system initialization, before any network services start. Which systemd target should the script be associated with?

A cron job that runs a backup script at 2 AM has not been executing. The syslog shows no errors from cron. What is the most likely reason the job is not running?

Which THREE are valid methods to view logs in a systemd-based system?

Refer to the exhibit. A technician sees that the httpd service has failed. Which command was used to view the detailed error log shown in the exhibit?

A Linux administrator is writing a Bash script to back up a directory. The script must continue running even if a particular command fails, but the administrator wants to log the error and take corrective action. Which of the following should be used to handle the error condition?

A system is experiencing high load average. The administrator runs 'vmstat 1 5' and sees a high 'wa' value. What does this indicate?

Which command creates a symbolic link named 'link.txt' that points to 'original.txt'?

A technician needs to identify the network interface configuration and IP address of a system. Which command provides the most comprehensive output for this task?

Refer to the exhibit. A Linux administrator created a systemd service file for a custom script. When starting the service, it fails with 'Unit myservice.service entered failed state.' Which of the following is the most likely cause?

A Bash script contains the following code: if [[ $# -eq 0 ]]; then echo 'No arguments'; fi. What does this code check?

A Linux administrator needs a scheduled job on a production server to run the backup script /usr/local/bin/backup.sh every day at 02:30, and the job must run as the root user regardless of who is logged in. Which single entry in /etc/crontab accomplishes this?

A DevOps engineer wants to reduce the size of a Docker image by combining build stages. Which Dockerfile feature should be used?

A Linux administrator needs to run a recurring backup script located at /usr/local/bin/backup.sh every day at 02:30. The system uses systemd and the administrator wants the job scheduled through a systemd timer rather than cron. Which combination of unit files must be created and enabled?

A junior administrator accidentally modified the /etc/sudoers file and now users report not being able to use sudo. Which command should be used to safely edit the sudoers file?

After a kernel upgrade, the system fails to boot. Which file should be edited to configure GRUB2 to boot into the previous kernel version by default?

Refer to the exhibit. An administrator wants to optimize a server running a high-throughput database application. Which command should be used to apply the recommended profile?

A Linux administrator needs to schedule a backup script to run every day at 2:30 AM. The script is located at `/usr/local/bin/backup.sh` and must run as the user `backupuser`. Which entry in the crontab for `backupuser` will accomplish this?

An administrator is tasked with creating a systemd service that runs a Python script after the network is available. The script must restart automatically if it fails. Which systemd service unit directive should be used to ensure restart on failure?

A Linux administrator is configuring a server to use a centralized authentication service. The security policy requires that user credentials are never sent in clear text and that the authentication traffic is encrypted. The administrator decides to use LDAP with TLS. Which command should be used to verify that the LDAP server's certificate is valid and that the TLS handshake succeeds?

An administrator needs to ensure that only users from the 'ops' group can SSH into a server. Which configuration in /etc/ssh/sshd_config accomplishes this?

A Linux administrator needs to view the kernel ring buffer messages to diagnose a hardware issue. Which command should the administrator use?

An administrator notices that a custom application uses port 8443/TCP. To allow external access, which firewalld command permanently opens this port in the default zone?

Match each Linux access control mechanism to its description.

The backup script above always outputs 'Backup failed' even when the tar command succeeds. Which of the following is the cause?

A server crashed with a kernel panic. After reboot, the administrator wants to analyze the crash dump. Which THREE actions should be taken to ensure a valid core dump is captured and accessible? (Choose THREE.)

A junior administrator is asked to verify that the integrity of a downloaded package file has not been altered in transit. The vendor publishes a SHA-256 checksum file alongside the package. Which command should the administrator run to compare the computed hash of the downloaded file against the published value?

An administrator notices that a user's crontab file is not executing. Which two commands can the administrator use to verify the user's crontab configuration? (Select TWO.)

A Linux administrator is troubleshooting a service that fails to start. The service unit file is present and enabled, but systemctl status shows 'failed' with exit code 203. Which command should the administrator run to view the most recent log messages specific to this service?

An Ansible playbook is being written to install the Nginx web server on a group of Ubuntu servers. Which module should be used in the playbook to install the package?

A Linux administrator needs to check the amount of free disk space on all mounted filesystems in a human-readable format. Which command should be used?

Drag and drop the steps to recover a forgotten root password in single-user mode in the correct order.

Which two of the following are valid methods to pass environment variables to a Docker container at runtime? (Select TWO.)

A Linux administrator is troubleshooting a service that fails to start. The service unit file contains 'User=appuser' and 'Group=appgroup'. The administrator runs 'systemctl start app.service' and sees the error 'Failed to determine user credentials: No such process'. Which of the following is the most likely cause?

A developer needs to grant a colleague read and write access to a directory /project, but the colleague should not have permission to delete any files created by the developer. The developer wants to set the directory so that all new files created in it automatically belong to the group 'project' and are writable by group. Which combination of configuration should be used?

A Linux server runs a critical service managed by a systemd service unit. The administrator needs to configure the service to automatically restart if it crashes, but only up to 3 times within a 30-second window. If the service restarts more than 3 times in 30 seconds, systemd should stop attempting to restart and leave the service in a failed state. Which set of directives should be added to the [Service] section of the unit file to achieve this behavior?

A user needs to view the first 15 lines of a large log file. Which command is most appropriate?

A developer wants to view the logs from a running Docker container named 'myapp'. Which docker command should be used?

An administrator wants to gather information about disk usage for a specific directory and its subdirectories. Which TWO commands can be used for this purpose? (Choose two.)

A Linux server is configured to use systemd. The administrator wants to ensure that a custom service named 'app.service' starts automatically at boot, even if it has been manually stopped. Which command should be used?

A Kubernetes administrator needs to expose a deployment named 'webapp' as a service accessible externally on port 80. Which kubectl command should be used?

Which THREE of the following are valid methods to troubleshoot a service that fails to start?

An administrator needs to update the package cache and upgrade all installed packages on a Debian-based system. Which TWO commands are appropriate for this task? (Select TWO.)

A company uses a Linux server running Ubuntu 22.04 LTS as a file server to share documents via Samba. The server has been in operation for over a year without issues. Following a routine system update that included kernel patches and updated Samba packages, users began reporting that they could no longer access any shared folders. The administrator verifies that the smbd and nmbd services are running and have not failed. The Samba configuration has not been changed recently. The server uses ufw as its firewall. When the administrator runs 'ufw status', the output shows that only SSH (port 22) is allowed. The administrator checks for SELinux but finds it is not installed; however, AppArmor is active and the smbd profile is in enforce mode. The administrator examines the AppArmor logs and finds no denials related to smbd. Which of the following is the most likely reason for the connectivity failure?

A system administrator wants to enforce a password policy requiring a minimum length of 12 characters, at least one uppercase letter, and one digit. Which PAM module should be configured?

An administrator needs to deploy a set of microservices using Docker Compose. The services require configuration values that vary between development and production environments. Which approach allows the administrator to override values without modifying the docker-compose.yml file?

A system administrator needs to run a script every 15 minutes. Which systemd unit type is used to schedule this?

A developer writes a Python script that uses the `requests` library to fetch data from an API. The script works on the developer's workstation but fails on the server with an import error. What is the most likely cause?

A technician is troubleshooting a service that fails to start at boot. Which systemctl command should be used to ensure the service starts automatically on subsequent boots?

A pod in the Kubernetes cluster is in CrashLoopBackOff. Based on the exhibit, what is the most likely cause?

A Linux administrator is troubleshooting a systemd service named 'webapp.service' that fails to start. The administrator runs 'systemctl status webapp.service' and sees that the service is in a failed state. Which TWO commands will provide additional diagnostic information about why the service failed? (Choose two.)

An administrator needs to view all current nftables rules. Which command should be used?

A server running RHEL 8 has intermittent network connectivity. The administrator wants to view the current DNS resolver configuration. Which file should be examined?

A Linux administrator is troubleshooting a server that is running out of disk space. Which TWO commands can be used to identify which directories or files are consuming the most space? (Choose two.)

A Linux server is experiencing slow boot times. The administrator wants to identify which systemd services are taking the longest to start. Which command should be used?

A Linux administrator uses Ansible to configure a fleet of web servers. A playbook task must copy a template file and then restart the nginx service only when the template content actually changes, avoiding needless restarts on every run. Which task construct enforces that behavior?

A system administrator is troubleshooting a service that fails to start. They want to see the recent logs for that specific service unit. Which journalctl command should be used?

An administrator is configuring iptables on a server. The requirements are: allow incoming SSH (port 22) from the 192.168.1.0/24 network, drop all other incoming traffic, and allow all outgoing traffic. Which three iptables rules achieve this? (Choose THREE.)

A user reports that they cannot access a web server at 192.168.1.100. The administrator wants to check if the server is reachable and measure round-trip time. Which command is most appropriate?

A system administrator notices that the httpd service fails to start. Which command should be used to view the most recent log entries for that specific service?

A system is running out of disk space in the /var/log directory. The administrator needs to temporarily free up space while preserving the latest log entries. Which approach is best?

A security auditor notices that users can set weak passwords on a Linux system. The administrator wants to enforce password complexity requiring a minimum of 12 characters, at least one uppercase letter, and at least one digit. Which PAM module should be configured in /etc/pam.d/common-password?

A Linux server is experiencing intermittent network connectivity issues. The administrator suspects that packets are being dropped due to a misconfigured firewall rule. Which command should the administrator use to view the current iptables rules and their packet counters?

A system administrator is working with compressed files. Which THREE commands can be used to view their contents? (Select THREE).

An administrator is troubleshooting a slow system. Which two commands can be used to identify processes consuming excessive CPU or memory? (Choose two.)

A Linux server experiences a kernel panic after a recent driver update. The system is still operational but unstable. Which command should be used to gather detailed information about the kernel modules currently loaded?

Given an ACL entry 'u:john:rwx' on a file, which command would remove only the ACL entry for user john without affecting other ACL entries?

Match each Linux filesystem to its typical use case.

A system administrator is troubleshooting a network issue where a server cannot reach external websites. The server can ping the default gateway and internal hosts. Which TWO commands should the administrator use to further diagnose the problem? (Choose TWO.)

An Apache web server hosted on a Linux system is unable to connect to a backend database server on port 3306. Based on the exhibit, which action should the administrator take to resolve the issue?

A Linux administrator needs to change the permissions of a file to be readable and writable by the owner, readable by the group, and no access for others. Which command accomplishes this?

A Linux administrator is troubleshooting a system that fails to mount the root filesystem during boot, dropping to an emergency shell. The administrator suspects that a recently added entry in /etc/fstab is incorrect. Which of the following commands should be used to verify the syntax and mountability of all entries in /etc/fstab without actually mounting them?

Which of the following commands can be used to display the contents of a file one page at a time? (Choose two.)

A developer is writing a Bash script that needs to parse command-line options with arguments, such as -f filename and -v. Which built-in command should be used to handle these options?

An administrator needs to run a backup script every day at 2:00 AM. The script is located at /usr/local/bin/backup.sh and is executable. The administrator considers several methods to schedule this task. Which method should the administrator use to ensure the script runs at exactly 2:00 AM every day without additional configuration overhead?

A system administrator wants to ensure that a service starts automatically at boot time using systemd. Which command should be used?

You are a Linux administrator at a company that runs a web application in Docker containers on a single host. The application consists of a front-end container (nginx) and a back-end container (node.js). Recently, after a system update, the front-end container fails to start with the error: 'Error response from daemon: driver failed programming external connectivity on endpoint frontend: (iptables failed: iptables --wait -t filter -A DOCKER ! -i docker0 -o docker0 -p tcp -d 172.17.0.2 --dport 80 -j ACCEPT: iptables: No chain/target/match by that name)'. Which action should you take to resolve the issue?

Which TWO commands can be used to display the amount of free and used memory on a Linux system?

A Linux administrator needs to configure sudo so that members of the group 'webadmins' can run any command as any user without being prompted for a password, but only on the host 'web01'. Which entry should be added to the sudoers file?

A user wants to run a command that will continue running even after the user logs out. Which command should be used?

A system administrator wants to display a list of all currently running processes, including those of other users, with full command lines. Which TWO commands can achieve this? (Select TWO.)

A system administrator wants to ensure that a container can access host devices such as USB drives. Which Docker run option should be used?

An administrator needs to generate a self-signed certificate valid for 365 days with a 2048-bit RSA key. Which OpenSSL command correctly creates both the private key and certificate in one step?

Which Dockerfile instruction sets the command to run when the container starts, but allows the user to override it when using docker run?

An administrator needs to view the last 20 lines of the systemd journal for the 'sshd' service. Which command should be used?

A system administrator runs the command 'chmod 4755 /usr/local/bin/backup'. What effect does this have on the file?

An administrator needs to ensure that the SSH service only allows key-based authentication and disables password authentication. Which configuration file and directive should be modified?

An administrator is configuring a custom kernel module to be loaded automatically at boot for a specialized hardware device. The module is named 'custom_hw'. Which file should be created to ensure the module is loaded at boot?

A system administrator installs a new application that is failing to write to its configuration file in /etc. SELinux is enforcing. Which command would show the relevant SELinux denials?

A file has permissions -rwxr-x---. The administrator wants to give the group write permission using symbolic mode. Which command is correct?

Refer to the exhibit. The system log is not updating. What is the cause?

A Linux administrator wants to harden a server against brute-force attacks. They decide to use fail2ban to monitor SSH authentication failures. After installing and enabling the fail2ban service, they need to verify that the SSH jail is active and correctly configured. Which command should they use to check the current status of the sshd jail?

Drag and drop the steps to create a new LVM logical volume in the correct order.

An administrator notices that a critical application server has become extremely slow, and load average has climbed above 40 on a 4-core system. The administrator wants to identify whether the bottleneck is CPU contention or processes stuck in uninterruptible sleep. (Choose two.)

An administrator needs to check the kernel ring buffer for hardware error messages from the current boot. Which command displays this information?

A server is experiencing frequent kernel panics. The administrator wants to capture the crash dump for analysis. Which kernel parameter must be set to enable crash dumps?

A developer wants to change all occurrences of 'foo' to 'bar' in a configuration file and save the changes in-place. Which sed command should be used?

An administrator is configuring a Linux firewall to allow incoming SSH (port 22) and HTTPS (port 443) traffic while denying all other incoming traffic. Using iptables, which set of commands achieves this?

Which TWO commands can be used to check the kernel version currently running on a system? (Choose two.)

An administrator wants to allow the user 'ops' to run only the command '/usr/bin/systemctl restart httpd' via sudo on a specific host 'webserver'. Which /etc/sudoers entry is correct?

Which file contains the hashed passwords and password aging information for user accounts?

A Docker container needs persistent storage that survives container restarts. Which of the following is the recommended method to achieve this?

A Linux administrator needs to add an ACL entry to grant read permission to a user named 'jdoe' on a file. Which TWO commands can be used to achieve this? (Select TWO).

An administrator wants to restrict SSH access to only users in the 'sshusers' group. Which configuration should be added to /etc/ssh/sshd_config?

Which directory in the Linux filesystem contains essential user command binaries that are needed for booting and repairing the system?

A user reports that a shell script fails with a 'Permission denied' error when executed, even though the file has the execute bit set for the owner. The administrator runs `ls -l script.sh` and sees `-rwxr-xr-x`. Which command should the administrator use to determine whether the filesystem is mounted with the `noexec` option?

A user reports that the 'backup.sh' script runs correctly when launched manually but silently does nothing when executed by cron at 02:00. The script relies on 'tar', which is found at /usr/bin/tar. Which action most directly resolves the failure?

A junior administrator needs to monitor system resource usage on a production server. Which TWO commands should the administrator use to check CPU and memory utilization in real-time? (Choose two.)

A Linux engineer needs to harden SSH access. Which TWO of the following settings should be configured in /etc/ssh/sshd_config to enhance security? (Select TWO.)

A Linux administrator needs to automate the deployment of a configuration file to fifty servers. The administrator wants to run a single command from a control node that copies the file to all servers in parallel and reports any failures. Which of the following tools is designed specifically for this task?

A system administrator wants to ensure that the /tmp directory is mounted with noexec to prevent code execution from temporary files. Which file should be modified to persist this across reboots?

A production web server intermittently stops responding for about 30 seconds at a time. The administrator runs 'vmstat 1' during an incident and observes the 'wa' column consistently above 80 while 'us' and 'sy' remain low. Which conclusion best describes the bottleneck?

A configuration-management playbook run by an administrator must install the nginx package only on hosts whose inventory group is webservers, and must restart the nginx service whenever the package installation changes the system. The administrator is using Ansible. Which pair of task attributes achieves both the conditional execution and the conditional restart?

An administrator notices that a service named 'httpd' is not running. They want to check its current status and, if inactive, start it. Which set of systemctl commands should be used?

A user reports that a Linux workstation fails to boot and displays 'Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)'. Which of the following is the most likely cause?

A custom application service 'myapp.service' fails to start on a RHEL 8 system with the error: "Failed at step EXEC spawning /usr/local/bin/myapp: Permission denied". The service runs as user 'myapp'. The binary /usr/local/bin/myapp has permissions 755 and is owned by root:root. The user myapp is not in the sudoers. The administrator checks SELinux and finds the binary has the context 'unconfined_u:object_r:usr_t:s0'. The service unit file does not specify any SELinux context. What is the most likely cause of the failure?

A Linux administrator is configuring a system to use a centralized authentication service. The requirement is that if the central server is unreachable, users should still be able to log in using cached credentials. Which PAM module should be configured to provide this functionality?

During boot, a Linux system displays a kernel panic with 'VFS: Unable to mount root fs on unknown-block(0,0)'. Which of the following is the most likely cause?

A system is experiencing boot failures. The administrator wants to view kernel messages from the current boot to diagnose the issue. Which two commands can be used to see these messages? (Choose two.)

A Linux administrator is troubleshooting a server that randomly drops SSH connections. The administrator suspects a network interface is experiencing errors or discards. Which command should be used to display detailed error and discard statistics for a specific network interface?

An application is being denied access to a file due to SELinux. Which command can be used to temporarily set the SELinux context of the file to match the expected type for the application?

A Linux administrator needs to configure sudo access for members of the 'wheel' group to run any command. Which two steps are required? (Choose TWO.)

A security audit identified that the /tmp directory is world-writable. Which THREE steps should be taken to secure /tmp on a Linux system? (Select THREE.)

A Linux administrator is troubleshooting a server that fails to mount a filesystem listed in /etc/fstab during boot, causing the system to drop into emergency mode. The administrator wants to prevent the system from entering emergency mode if this particular mount fails, while still attempting to mount it. Which fstab option should be added to the mount entry?

A Linux server's root filesystem was accidentally filled to 100% capacity by runaway application logs. After the administrator deletes several large log files with rm, df -h still reports the filesystem at 100% usage. Which command should the administrator use to identify the process that is holding these deleted files open?

Which THREE tools are commonly used for configuration management?

A Linux administrator is troubleshooting a service that fails to start. They want to view the most recent log entries for that service using systemd's journal. Which command should they use?

An administrator needs to generate a self-signed certificate and private key for an internal web server. Which OpenSSL command creates both in one step?

An administrator wants to find all files in the current directory tree that are larger than 100 MB and have the .log extension. Which find command will accomplish this?

An administrator configures /etc/ssh/sshd_config with the following settings: PermitRootLogin no, PasswordAuthentication no, AllowUsers alice bob, MaxAuthTries 2. After restarting sshd, which of the following is true?

A Linux server has a single disk /dev/sda with LVM. The root logical volume is nearly full and the administrator adds a new disk /dev/sdb to extend it. After creating a physical volume on /dev/sdb and adding it to the volume group, which command should be used to extend the root logical volume and its filesystem in one step?

A Linux administrator is automating user account creation. The script reads a list of usernames from a file and creates each account. The administrator wants the script to continue processing remaining users even if one useradd command fails due to a duplicate username. Which Bash construct should be used to run useradd and handle the failure without aborting the script?

Which command is used to display the contents of a compressed log file without decompressing it?

A user wants to view the contents of a text file one page at a time. Which two commands can be used? (Choose two.)

Drag and drop the steps to configure SELinux to allow a custom web application to listen on port 8080 in the correct order.

A senior administrator is troubleshooting a shell script that fails to execute properly. The script starts with #!/bin/bash and has execute permissions. Which of the following could cause the script to fail to run when invoked as ./script.sh?

A Linux administrator needs a service to be started automatically at boot and then started immediately without rebooting. The service unit file is located at /etc/systemd/system/myapp.service. Which command should the administrator run to accomplish both tasks?

A system administrator is troubleshooting a service that fails to start with the error 'Unit failed to load: Invalid argument'. The service file is located in /etc/systemd/system. What is the most likely cause?

An administrator runs the command `ls -l /data/file.txt` and sees the output: `-rw-r-----+ 1 root project 1024 Mar 15 10:00 file.txt`. The administrator wants to view the current ACL entries on this file. Which command should be used?

SELinux is currently in enforcing mode. A service is being blocked by SELinux. Which command can analyze the audit log and suggest the minimum policy changes to allow the service?

A Linux administrator is troubleshooting a systemd service that fails to start. The service unit file is located at /etc/systemd/system/myapp.service. Which two commands should the administrator use to reload the systemd manager configuration and then restart the service? (Choose two.)

A system administrator is configuring centralized logging for a cluster of web servers. Each web server runs rsyslog and needs to forward its Apache access logs to a central log server at 192.168.1.100 over UDP port 514. The administrator adds the following line to /etc/rsyslog.conf on each web server: '*.* @192.168.1.100:514'. After restarting rsyslog, no logs appear on the central server. The administrator checks the network connectivity and finds that the central server is reachable and listening on UDP 514. Which additional configuration is most likely required on the web servers to forward the Apache logs?

A Linux administrator is troubleshooting a service that fails to start at boot. The service unit file is present in `/etc/systemd/system/` and has been enabled. Running `systemctl status myservice` shows it as `inactive (dead)`. Which command should the administrator run to see the most recent boot messages for this service?

A systems administrator creates a bash script that processes log files. The script uses a for loop to iterate over files in /var/log and runs a command on each. Which of the following would prevent the script from failing if no files match the pattern?

A technician wants to check the disk I/O statistics, focusing on the average I/O wait time and utilization percentage. Which command provides this information?

A Linux administrator notices that a production server's root filesystem is 100% full, but du reports only 40 GB used on a 100 GB partition. Which command should the administrator use to identify deleted files still held open by running processes?

Which command will run a container in detached mode with the name 'web' and map host port 8080 to container port 80, using the nginx image?

Which directory in the Filesystem Hierarchy Standard (FHS) contains essential user commands available to all users, such as 'ls' and 'cp'?

An administrator wants to change the default systemd target to multi-user.target so the system boots to a text console. Which command should be used?

An administrator wants to run a script on multiple remote servers using Ansible. The script requires a variable that differs per host. Where should the administrator define this variable to follow best practices?

An administrator is troubleshooting a boot issue. The system boots to a console with limited functionality. Which systemd target should be used to bring up the system with network and multi-user support?

An administrator needs to grant read and write access to the 'developers' group on a directory while preserving existing permissions for the owner and others. Which TWO commands can be used to modify ACLs? (Choose two.)

A security administrator is hardening a Linux server that uses firewalld. The server hosts a web application that must be accessible only from the internal network 192.168.1.0/24 on port 443. The administrator wants to implement this using a rich rule in the public zone and ensure it persists across reboots. Which sequence of commands should the administrator use?

A team uses Ansible for configuration management. A playbook fails with the error 'ERROR! Syntax Error while loading YAML script'. Which of the following is the most likely cause?

A security policy requires that user passwords must expire every 90 days. Which command can enforce this policy for user 'jsmith'?

A system administrator is tuning a server for a high-performance computing workload and needs to disable NUMA (Non-Uniform Memory Access) at boot to improve memory access latency. Which kernel boot parameter should be added to the GRUB_CMDLINE_LINUX line in /etc/default/grub?

A user is unable to create new files in a directory. Which command can the administrator use to view the Access Control Lists (ACLs) associated with that directory?

A Linux administrator is configuring a persistent mount for a new 2TB XFS filesystem on /dev/sdb1 so it mounts automatically at /data with quota accounting enabled. The administrator edits /etc/fstab and adds the entry, then runs mount -a to validate it. Which fstab field combination correctly applies user and group quota accounting on this XFS mount?

A technician needs to create a new ext4 filesystem on /dev/sdb1 and mount it persistently at /mnt/data. Which set of commands accomplishes this?

A Linux administrator is configuring secure remote access to a server. Which three of the following are recommended best practices for securing SSH? (Choose three.)

Which Kubernetes resource is used to store non-sensitive configuration data as key-value pairs that can be consumed by pods?

An administrator needs to create a hard link to an existing file. Which two statements are true about hard links? (Choose two.)

A DevOps engineer is writing a unit file for a systemd service that should start after the network-online.target. Which directive should be added to the [Unit] section?

A Linux server's /var/log partition is 100% full and rsyslogd has stopped writing logs. The administrator needs to find which directories under /var/log consume the most space without deleting anything. Which command should the administrator run?

An administrator wants to find all files larger than 100MB in the /var directory. Which command should be used?

A system is experiencing high memory usage. The administrator wants to see a brief summary of memory usage in human-readable format, including buffers and cache. Which command is most appropriate?

A bash script uses a for loop to iterate over files in a directory. Which of the following correctly assigns each filename to the variable FILE?

A Linux administrator needs to configure a system to use a central authentication service. The service requires that user credentials are sent over the network in an encrypted format and that the client validates the server's certificate. Which of the following should the administrator configure?

A company is implementing a security policy that requires all files created in a shared directory /data to be owned by the group 'engineers' and have group read/write permissions, regardless of the user's umask. Which approach should be used?

Match each Linux kernel parameter category to its description.

A Linux administrator needs to grant temporary, time-limited administrative access to a contractor on a production server. The contractor must be able to run only `/usr/bin/systemctl restart nginx` as root without a password, and all actions must be logged. The administrator plans to use sudo. Which two steps are required to meet these requirements? (Choose two.)

A process is consuming excessive CPU and needs to be terminated immediately. The PID is 1234. Which command will terminate the process with the most forceful signal?

A Linux server's root filesystem is filling rapidly. The administrator suspects a process is writing to a deleted file that still holds space. They want to identify which running process has an open file descriptor to a deleted file. Which command should they use?

A system administrator needs to monitor real-time process information and system resource usage. Which two commands can be used for this purpose? (Choose two.)

An administrator needs to generate a self-signed certificate and private key for a web server. Which openssl command accomplishes this?

Which command is used to display the current process hierarchy in a tree format?

A Linux server is experiencing intermittent connectivity issues. The administrator reviews the system logs and finds the following messages: 'NETDEV WATCHDOG: eth0: transmit queue 0 timed out'. Which THREE actions are likely to resolve this issue? (Choose three.)

A user cannot write to a directory that has permissions 755. The user is not the owner but belongs to the group. Which command would allow the user to write?

A security audit reveals that the /etc/shadow file has permissions 777. Which command should be used to correct this vulnerability?

Which log file typically records authentication failures and successes on a Debian-based system?

An Ansible playbook is being written to manage web servers. Which TWO modules can be used to ensure a package is installed? (Select TWO.)

Which command displays the current SELinux mode?

A junior administrator is tasked with setting up a file server using NFS on a Linux server. The /etc/exports file currently contains: /srv/nfs *(rw,sync,no_subtree_check). The administrator wants to restrict access to only the 192.168.10.0/24 network and require clients to use a privileged port (less than 1024) for added security. Additionally, the administrator wants to prevent root users on the client from having root access to the NFS share. Which exports configuration meets these requirements?

Which command will display the disk usage of each directory in the current directory, in human-readable format?

A systems administrator needs to automate the execution of a backup script every day at 2:00 AM using a systemd service. Which unit type should the administrator create?

A Linux server's root filesystem was extended with LVM, but after a reboot users report that only the original capacity is available again. Running 'df -h' shows the mount smaller than the logical volume, and 'lvextend' completed successfully before the reboot. Which command should the administrator run to make the filesystem use the additional space on an XFS root volume?

Which command displays the disk usage of files and directories in a human-readable format (e.g., KB, MB)?

A Linux administrator needs to grant a user named 'bob' the ability to run the /usr/bin/systemctl command as root without being prompted for a password. Which entry should be added to the sudoers file to accomplish this?

A Linux administrator is hardening a server and needs to ensure that the system is protected against unauthorized access. The administrator wants to implement account lockout after multiple failed login attempts and enforce password complexity. Which TWO actions should the administrator take to achieve these goals? (Choose two.)

Refer to the exhibit. An API call returns HTTP 200 but an empty body. What is the most likely cause?

A user wants to execute a command inside a running Docker container named 'db'. Which command should be used?

A Linux administrator needs to configure a service to run as a specific user and group, and to restart automatically on failure. The service is managed by systemd. Which directive in the unit file should the administrator use to specify the user and group, and which directive to ensure automatic restart?

A security audit reveals that the system's PAM configuration does not enforce password complexity. Which PAM module and configuration line should be added to /etc/pam.d/common-password to require at least one uppercase letter, one digit, and a minimum length of 12 characters?

A Linux administrator maintains a Bash deployment script that runs unattended from cron. The script currently contains `set -e` and `set -u`, but it silently continues past a failing command inside a pipeline such as `tar -czf backup.tgz /srv | tee /var/log/backup.log`. The administrator wants the script to abort whenever any element of that pipeline returns a non-zero status. Which line should be added to the top of the script?

A server running RHEL 8 fails to boot with a 'Dependency failed for /data' error. The /data filesystem is an ext4 partition on /dev/sdb1. Which sequence of steps should be taken to repair the filesystem?

A database server is running slow. The administrator uses iostat and notices high await times on the disk. Which of the following best explains the implication of high await?

An administrator is troubleshooting a DNS issue and needs to query the authoritative name servers for example.com. Which dig command should be used?

A containerized application is consuming excessive memory on a Linux host running Podman. Which command sets a memory limit of 512 megabytes when running a container?

An administrator needs to apply a set of permissions to an existing directory and all its contents, setting the owner to 'rwx', group to 'rx', and others to '---'. Additionally, newly created files within the directory should inherit the group. Which commands should the administrator run? (Assume the directory is /data, and the group is 'staff'.)

A user wants to create a symbolic link to a file named 'original' in their home directory. Which command creates a symbolic link named 'link'?

Which command will display the disk usage of each file and directory in the current directory?

A system administrator needs to collect performance data over time to analyze CPU and memory usage trends. Which THREE of the following commands can be used to gather historical performance data? (Choose THREE.)

A Linux administrator is troubleshooting a server that becomes unresponsive under load. They want to capture a live, per-second view of CPU usage broken down by individual processor cores, along with load averages. Which command should they use?

A Linux administrator needs to configure a system so that the service `httpd` starts automatically when the system boots into the default target. Which command should the administrator use?

Which tool is used for encrypting files with public-key cryptography on Linux systems?

Which TWO commands can be used to display the current kernel version on a Linux system?

Which TWO statements about container security are correct when using Docker? (Choose two.)

A Linux administrator needs to create a new user account 'jdoe' with a home directory /home/jdoe and the default shell /bin/bash. Which command will accomplish this?

A Linux administrator is investigating why a user cannot log in via SSH. The SSH service is running, and the network is reachable. The administrator suspects that the user's account is locked or expired. Which command should they use to check the account status and expiration details for the user 'jdoe'?

A Linux administrator is diagnosing a system that occasionally hangs during boot. The administrator suspects a hardware issue. Which command will display kernel ring buffer messages, including hardware detection and driver errors, from the current boot?

An Ansible playbook fails with a syntax error. Which command validates the playbook syntax without running it?

Which three are valid systemd unit types?

A system administrator is writing an Ansible playbook to manage a web server. Which three of the following are valid Ansible modules for system administration? (Choose THREE.)

A server has a volume group 'vg_data' with a single logical volume 'lv_data' of 100GB mounted at /data. The filesystem on lv_data is XFS. The administrator needs to extend it to 150GB. A new 60GB disk /dev/sdc has been added and partitioned as LVM. The administrator runs `pvcreate /dev/sdc1`, then `vgextend vg_data /dev/sdc1`, then `lvextend -L +50G /dev/vg_data/lv_data`. The administrator runs `df -h /data` and sees that the filesystem still shows 100GB. Which command should be run next?

In the exhibit, what does 'Tasks: 11 (limit: 512)' indicate?

A Bash script uses getopts to parse command-line options. The options are -a (requires an argument) and -b (flag). Which code correctly implements this and stores the argument for -a in $optarg?

A company's security policy requires that all user passwords must expire every 90 days. The administrator runs 'chage -M 90 jdoe' for user jdoe. Which additional step ensures that the password expiration policy is enforced for all new users?

A Linux engineer is troubleshooting a cron job that does not execute as expected. The crontab entry reads: '*/5 * * * * /usr/local/bin/backup.sh'. The script runs manually when executed as root. Which of the following is the most likely cause?

A bash script needs to test whether a string variable $NAME is non-empty and equals 'admin'. Which of the following conditionals is correct?

A system is experiencing high disk I/O wait. Which command can provide disk I/O statistics such as requests per second and average wait time?

An administrator needs to give a user read and write access to a file without changing the file's group or adding the user to any group. Which method should be used?

Which THREE are valid SELinux modes?

An administrator is writing a Dockerfile. They need to set a default command that can be overridden when running the container. Which instruction should be used?

A user has a file with permissions set to 644. Which of the following commands will add the setuid permission to the file? (Choose two.)

A Linux administrator notices that the /home filesystem is full. They want to identify which top-level directories under /home are consuming the most disk space. Which command should they run?

A Linux server's clock drifts by several minutes each day. The administrator runs `timedatectl` and sees that NTP synchronization is enabled but the system clock is not synchronized. The server can reach the internet, and `chronyd` is running. Which command should the administrator use to verify which NTP sources are currently reachable and their stratum levels?

A security analyst is investigating a potential breach and needs to examine user login history. Which THREE commands or log files provide information about user logins? (Select THREE.)

An administrator needs to replace all occurrences of 'oldhost' with 'newhost' in the configuration file /etc/hosts. Which command will perform the replacement and save the changes directly to the file?

A Linux administrator is hardening an SSH server. Which two of the following settings should be applied to /etc/ssh/sshd_config to improve security?

A Linux administrator needs to change the hostname of a system to 'webserver01' permanently. The system uses systemd. Which command should the administrator use?

A DevOps team uses Podman to run containers rootlessly. Which TWO of the following characteristics apply to rootless Podman compared to Docker? (Select TWO).

An administrator wants to ensure that only users in the 'wheel' group can use the sudo command. Which directive in /etc/sudoers enables this?

A security audit reveals that the /etc/shadow file has permissions 0644 and is owned by root:shadow. The auditor states that this is a security risk because any local user can read password hashes. The administrator wants to fix the permissions to ensure that only root and the shadow group can read the file, and no one else can read it. Additionally, the administrator wants to set the immutable attribute on the file to prevent accidental modification. Which set of commands achieves the desired state?

An administrator needs to run a script '/usr/local/bin/cleanup.sh' every day at 2:30 AM. Which crontab entry is correct?

A systems administrator needs to ensure that a custom service runs with a specific priority on a Linux server. Which command should the administrator use to achieve this?

An administrator needs to configure SELinux to allow the Apache HTTP server to connect to a database server. Which SELinux boolean should be enabled?

A Linux engineer is investigating high disk I/O on a server. Which command provides disk I/O statistics including %util, await, r/s, and w/s?

A Linux administrator is troubleshooting a server that intermittently becomes unresponsive. The administrator suspects a memory leak. Which command should be used to monitor memory usage over time and identify the consuming process?

A system administrator notices that the root filesystem is at 95% capacity. Which command should be used to identify the directories consuming the most space?

Which TWO tools are specifically designed to detect rootkits on a Linux system?

Refer to the exhibit. What is the total amount of RAM installed on the system?

A Linux system has a directory with permissions drwxr-xr-x. A user in the group 'dev' tries to create a new file inside this directory. Which permission is missing that prevents the user from creating the file?

A Linux engineer needs to restrict resource usage for users in the 'developers' group. Which TWO files or commands can be used to set ulimit values?

Refer to the exhibit. A web application running under Apache cannot write to /var/log/app.log. The file has permissions 664 and is owned by apache. What is the correct action to allow writes while maintaining SELinux policies?

A system administrator wants to limit the CPU and memory usage of a specific service to prevent it from affecting other processes. Which Linux feature should be used?

An administrator needs to add an ACL entry to a file that grants the user 'john' read and write permissions. The file currently has no ACLs. Which command should the administrator use?

Which TWO of the following are valid methods for debugging a Bash script? (Choose TWO.)

A Linux administrator receives reports that a database server becomes unresponsive every day around 02:00. Reviewing logs, the administrator notices repeated messages about 'blocked for more than 120 seconds' and high I/O wait. Which command should be used to identify which process is generating the most disk I/O during this period?

A compliance auditor requires that a Linux server's /home directory be mounted with options that prevent users from executing setuid binaries stored there and from creating device files. The administrator is editing /etc/fstab for the /home entry. Which TWO mount options should be added to meet these requirements? (Choose two.)