The Linux Operating System

Which command lists all files in a directory including hidden ones?

Which TWO of the following are examples of Linux distributions?

A helpdesk technician is preparing a Linux workstation for a new employee. The employee needs to know which account they are currently logged in as, without opening any graphical tools. Which single command should the technician recommend to display the current user's login name?

A new administrator needs to grant a colleague the ability to run a specific backup script as root without sharing the root password, while keeping the action auditable and restricted to that one command. The server already has the sudo package installed and the colleague has a normal user account. Which approach best meets these requirements?

A consultant is auditing a Linux workstation and finds that a regular user's home directory contains a file named .bashrc and a file named .profile. The user reports that environment variables set in .profile are not present in new interactive terminal windows opened from the desktop, yet aliases from .bashrc work. Which explanation best accounts for this behavior?

A new administrator is learning how Linux organizes its filesystem. She must identify which of the following statements about the Filesystem Hierarchy Standard (FHS) are correct. (Choose two.)

Which TWO of the following are examples of common Linux filesystems?

A help-desk analyst needs to see which processes are consuming the most CPU and memory in real time, and must be able to sort and kill a runaway process interactively. Which utility best fits this requirement?

A user needs to change their own password on a Linux system. Which command should they use?

You need to determine the UUID of a partition to add it to /etc/fstab. Which command should you use?

A user reports that a script located in their home directory will not run when they type its name, even though the file exists and has execute permission. The user is currently in that home directory. Which action explains why the script is not found and how to run it?

You need to ensure that a server's time is synchronized with an external time source to prevent authentication errors. Which daemon is responsible for this?

You have added a new hard drive to your Linux server, but the system does not automatically recognize the device. What is the first step you should take to verify if the kernel detects the hardware?

A support engineer is handed a Linux server and needs to determine which user account is currently logged in on a remote SSH session before performing maintenance, so they can notify the right person. Which command most directly reports the usernames of users currently logged into the system?

A system administrator needs to identify which process is listening on TCP port 80 on a Linux server. Which command is most appropriate?

Which TWO of the following are valid ways to view system logs?

An administrator wants to view the current system load and active processes. Which utility is the most appropriate for a real-time monitor?

Which THREE of the following are components of a standard network configuration?

You are setting up a local network and need to verify the path traffic takes to reach a remote host. Which command should you use?

A systems administrator is documenting a server and wants to record which kernel release is currently running, including any distribution-specific patch level, for compatibility checks with a third-party driver. Which command should be used to display this information?

Which command is used to display the current directory path in the terminal?

A user wants to change the permissions of a file named 'data.txt' so that the owner can read and write, the group can read, and others have no access. Which command achieves this?

A Linux administrator needs to check which shell is currently assigned to the user account 'jdoe' in the system's user database, without logging in as that user. Which command will display this information?

A Linux administrator is auditing user accounts and needs to identify which files store local user account and hashed password information on a typical distribution. (Choose two.)

A developer needs to know the kernel version currently running on the server. Which command provides this information?

You are trying to troubleshoot why a user cannot connect to your server via SSH. You want to see if the SSH daemon is listening on the appropriate port. Which command should you run?

A Linux administrator is preparing a machine that must run headless as a file server. She needs to identify which of the following are characteristics of a Linux server installation rather than a typical desktop installation. (Choose two.)

Which TWO of the following commands help in identifying hardware on a system?

You suspect that a process is consuming too much CPU. Which command allows you to sort active processes by CPU usage?

A Linux administrator is reviewing the boot process on a server that uses systemd. She wants to determine which target the system will boot into by default and confirm the current default setting. Which command should she use?

A Linux administrator is reviewing how environment variables affect command execution. Which TWO of the following statements about environment variables are correct? (Choose two.)

A Linux administrator is troubleshooting a server that fails to boot completely. The system starts but drops into an emergency shell. Which command should the administrator use to view the most recent kernel messages that might indicate the cause?

A junior administrator is asked to determine which shell will be launched for a user named 'alex' upon login. The administrator inspects the /etc/passwd file and sees the following line: alex:x:1001:1001:Alex Smith:/home/alex:/bin/bash. Which field in this line specifies the login shell?

Which THREE commands can be used to display information about system memory?

A server is running out of disk space. Which command allows you to view the space usage of directories in a human-readable format?

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

A user wants to check the amount of free disk space on all mounted filesystems in a human-readable format. Which command should they use?

A helpdesk technician is asked to confirm which Linux kernel is currently running on a production web server so they can compare it against a vendor's supported-kernel list. They only have a standard shell session and want the most direct command that prints the running kernel release string. Which command should they use?

While exploring a Linux system, a new administrator runs `ls -l /etc/shadow` and sees that the file is owned by root and group shadow, with permissions `rw-r-----`. They want to understand which user accounts on the system are currently configured with a valid password hash versus those that are locked. Which command best lists only the accounts that have a real password hash set in `/etc/shadow`?

A system administrator is troubleshooting a Linux server that has become unresponsive. The administrator wants to view a snapshot of all currently running processes, including those not attached to a terminal, along with their process IDs and CPU usage. Which command should the administrator use?

A helpdesk technician is asked to install a Linux distribution on a spare workstation for a new employee who needs a full desktop environment. The technician wants to minimize the time spent selecting packages during installation. Which type of Linux distribution should the technician choose?

Which TWO of the following directories are usually located at the root of a Linux filesystem?

A technician has just unpacked a new server and needs to confirm which physical architecture the CPU reports so they can request the matching RPM package. Which command will display the machine's hardware architecture, such as x86_64?

A Linux system administrator notices that the /var/log directory is filling up quickly. They want to find the largest files within that directory tree to identify what is consuming space. Which command will accomplish this?

A consultant is preparing a presentation about the Linux ecosystem. She needs to explain the relationship between the kernel and a complete Linux distribution. Which statement best describes this relationship?

A user wants to view the contents of a text file named 'notes.txt' one page at a time, and also be able to scroll backward and forward within the file. Which command is best suited for this task?

A user reports that a script stored on a mounted USB drive will not execute when invoked by name, even though it runs when called explicitly through the shell with bash script.sh. The file has execute permission set for the user. Which is the most likely cause?

A system administrator is checking for hardware errors in the logs. Where are general system messages usually stored?

Which TWO of the following are considered hardware components?

A Linux administrator needs to grant a contractor temporary read and write access to a project directory without adding the contractor's account to a shared group or changing ownership of existing files. Which approach best meets this requirement while following standard Linux permission practice?

Which TWO of the following tools allow you to manage disk partitions?

A junior admin is confused about the difference between software RAID and hardware RAID. Which of the following is a primary characteristic of software RAID?

A technician is preparing a presentation on how Linux organizes its filesystem and wants to describe the role of the Filesystem Hierarchy Standard. Which two statements accurately describe the FHS as it applies to mainstream Linux distributions? (Choose two.)

You need to change the ownership of a file to user 'admin'. Which command is the correct way to do this?

A help desk technician receives a call from a user who complains that their Linux workstation feels sluggish. The technician wants to see a dynamic, real-time list of processes sorted by CPU usage. Which command should the technician run?

You are managing a Linux server and need to confirm the IP address assigned to the eth0 interface. Which command is most appropriate on modern distributions?

A Linux administrator needs to check how much free space remains on each mounted filesystem before deploying a large application. The administrator wants a quick, human-readable summary showing used and available space per mount point. Which command should be used?

Which THREE of the following files/commands are involved in system startup or services?

An administrator needs to monitor network traffic in real-time on a specific interface. Which tool is commonly used to capture and display packets?

A user needs to find all files in the /var/log directory that have been modified in the last 24 hours. Which command will accomplish this?

A Linux user wants to create a new directory named 'projects' and then move an existing file named 'report.txt' into it. Which two commands will accomplish these tasks? (Choose two.)

A system administrator wants to check the partition table of a specific disk. Which tool is used for this?

Which THREE of the following items are typically found in the /etc directory?

A Linux administrator is reviewing user account files and needs to understand where user information is stored. Which TWO of the following files contain user account details? (Choose two.)

What is the purpose of the /proc directory in Linux?

Which TWO commands are commonly used to check network connectivity to a host?

A small business owner wants to implement a server that allows for long-term support and stability for critical financial applications. Which distribution strategy should they prioritize?

A technician needs to identify the amount of RAM installed in a server without opening the chassis. Which command provides this information from the command line?