XK0-006 Practice Test 32 — 15 Questions

Question 1

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

Accepted Answer

more. Both 'more' (B) and 'less' (E) are pagers that display a file one screenful at a time, pausing so the user can scroll forward (and in less, backward) through the content, which is exactly what 'view a file page by page' means. 'more' shows the file page by page and advances with the spacebar, while 'less' is the more capable pager that also supports backward scrolling and searching. The other commands do not paginate: 'tail' (A) prints only the last lines (default 10), 'cat' (C) dumps the entire file to standard output at once, and 'head' (D) prints only the first lines (default 10).

Answer

tail

Answer

cat

Answer

head

Question 2

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?

Accepted Answer

COPY config.txt /app/ and EXPOSE 8080. COPY adds files from the build context, and EXPOSE documents the port. Other instructions serve different purposes.

Answer

ADD config.txt /app/ and WORKDIR 8080

Answer

ADD config.txt /app/ and RUN expose 8080

Answer

COPY config.txt /app/ and CMD 8080

Question 3

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

Accepted Answer

ChrootDirectory /home/%u. The ChrootDirectory directive in /etc/ssh/sshd_config specifies the path to the directory that will be used as a chroot jail for the user. When set to /home/%u, %u is replaced by the username, confining the SFTP user to their home directory. This is the standard way to restrict an SFTP user's file system access to a specific directory tree.

Answer

Subsystem sftp internal-sftp

Answer

ForceCommand internal-sftp

Answer

Match Group sftpusers

Question 4

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?

Accepted Answer

aa-complain /usr/bin/application. `aa-complain /usr/bin/application`, is correct because it sets the specified AppArmor profile to complain mode, which logs policy violations without blocking access. This allows the administrator to identify which accesses the application needs by reviewing the generated log entries, typically in `/var/log/syslog` or via `ausearch`, while the application continues to run.

Answer

systemctl restart apparmor

Answer

aa-enforce /usr/bin/application

Answer

apparmor_parser -r /etc/apparmor.d/usr.bin.application

Question 5

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?

Accepted Answer

ausearch -m avc | audit2allow -M myapp. The audit2allow workflow is the standard way to convert SELinux AVC denial messages into a loadable policy module. Piping ausearch output into audit2allow -M myapp generates a .te source file and compiles it into a myapp.pp module that can be installed with semodule -i, granting exactly the denied write permission.

Answer

chcon -t var_log_t /var/log/app.log

Answer

setsebool -P httpd_unified 1

Answer

restorecon -v /var/log/app.log

Question 6

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

Accepted Answer

apt. The apt module is for Debian-based systems, and yum is for Red Hat-based systems. Both manage packages.

Answer

copy

Answer

service

Answer

template

Question 7

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

Accepted Answer

for f in *.txt; do. The `for f in *.txt; do` loop is correct because it uses shell globbing to expand `*.txt` into a list of all .txt filenames in the current directory, then iterates over each filename. This is the standard and most efficient way to process a set of files matching a pattern in Bash and POSIX shell scripting.

Answer

while read line; do

Answer

select option; do

Answer

until condition; do

Question 8

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?

Accepted Answer

mtr target. The mtr command combines the functionality of ping and traceroute by continuously sending packets to a target and displaying per-hop latency and packet loss, making it ideal for monitoring intermittent network issues over time.

Answer

tcpdump -i any host target

Answer

ping -f target

Answer

traceroute -n target

Question 9

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.)

Accepted Answer

top. The `top` command provides a real-time, dynamic view of system processes, displaying CPU usage per process, memory utilization, and overall system load. It continuously updates, making it ideal for monitoring resource usage on a production server.

Answer

df

Answer

uptime

Answer

lsof

Question 10

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?

Accepted Answer

oneshot. The `oneshot` unit type is correct because it is designed for services that run a single task to completion and then exit, making it ideal for a one-time script that must execute after the network is up. In systemd, `oneshot` units can be configured with `RemainAfterExit=no` (the default) to indicate they do not need to stay running, and they support ordering dependencies like `After=network-online.target` to ensure the network is available before the script runs.

Answer

forking

Answer

exec

Answer

simple

Question 11

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?

Accepted Answer

Use cron to run at 9:00 on weekdays, and include a test in the script that checks a holiday list. Cron can schedule the script to run at 9:00 AM on weekdays using the day-of-week field (e.g., `0 9 * * 1-5`), and the script itself can check a holiday list (e.g., a file or API) to exit early on holidays. This approach cleanly separates scheduling from holiday logic, avoiding cron's lack of built-in holiday awareness.

Answer

Use systemd timers with a calendar specification that excludes holidays

Answer

Use cron to run at 9:00 every day, and include conditional logic to abort on weekends

Answer

Use `at` to schedule the job individually each weekday morning

Question 12

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?

Accepted Answer

find /var -mmin -30 -size +10M. The correct command is `find /var -mmin -30 -size +10M`. The `-mmin -30` option tells find to match files modified less than 30 minutes ago (the minus sign means 'less than'), and `-size +10M` matches files larger than 10 megabytes. This combination precisely meets the requirement of files modified within the last 30 minutes and larger than 10MB.

Answer

find /var -mmin 30 -size +10M

Answer

locate /var -mmin -30 -size +10M

Answer

find /var -mtime -30 -size +10M

Question 13

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

Accepted Answer

pre-commit. The pre-commit hook runs before a commit is created, making it the correct choice for automatically running tests before every commit in a local Git repository. This hook can validate code quality, run unit tests, or check for syntax errors, and if it exits with a non-zero status, the commit is aborted.

Answer

post-receive

Answer

post-commit

Answer

pre-push

Question 14

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?

Accepted Answer

The SELinux context of the binary is incorrect; it should be bin_t.. The error occurs because SELinux is enforcing and the binary has the type 'usr_t', which is not allowed to be executed by the service's domain (probably init_t or custom domain). The correct type for executables in /usr/local/bin is 'bin_t'. The solution is to restore the SELinux context to the default for binaries using `restorecon -v /usr/local/bin/myapp` or changing it to bin_t. Option A is incorrect because permissions allow execution. Option C is unlikely because /usr/local/bin is in PATH. Option D is incorrect as user has execute permission.

Answer

The user myapp does not have read access to the binary.

Answer

The binary is located in a directory that is not in the systemd safe path.

Answer

The binary is not executable by myapp due to file permissions.

Question 15

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

Accepted Answer

CMD. CMD provides defaults for an executing container. If CMD is used, it can be overridden by command-line arguments to docker run. ENTRYPOINT, on the other hand, is not easily overridden without --entrypoint.

Answer

RUN

Answer

STARTUP

Answer

ENTRYPOINT