XK0-006 Practice Test 9 — 10 Questions

Question 1

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?

Accepted Answer

grep -rin 'ERROR' /var/log. The command 'grep -rin ERROR /var/log' combines -r (recursive search through directories), -i (case-insensitive match), and -n (print line numbers). This searches every file under /var/log for 'ERROR' regardless of case and prefixes each match with its line number, exactly matching the requirement.

Answer

grep -vi 'ERROR' /var/log

Answer

grep -rn 'ERROR' /var/log

Answer

find /var/log -name '*ERROR*'

Question 2

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?

Accepted Answer

renice -n 10 -p 1234. renice is used to change the nice value of an existing process. A higher nice value means lower priority.

Answer

renice -n -10 -p 1234

Answer

chrt -p 10 1234

Answer

nice -n 10 -p 1234

Question 3

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?

Accepted Answer

docker run -d -p 8080:80 --name webapp nginx. `docker run` is the command that creates AND starts a container in one step, and the `-d` flag detaches it to run in the background. The `-p 8080:80` flag maps host port 8080 to container port 80, and `--name webapp` assigns the container name. This is the canonical single-command way to launch a named, port-mapped, background container from the nginx image.

Answer

docker start -d -p 8080:80 --name webapp nginx

Answer

docker create -d -p 8080:80 --name webapp nginx

Answer

docker compose up -d -p 8080:80 --name webapp nginx

Question 4

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?

Accepted Answer

AppArmor. AppArmor (B) is a Linux Security Module that enforces mandatory access control by applying per-program profiles that restrict a daemon's file, network, and capability access, so it directly confines a vulnerable service. SELinux (C) is likewise an LSM implementing MAC through type enforcement, roles, and security contexts, and it is commonly used to sandbox daemons on Linux servers. Both are kernel-level MAC frameworks, which is exactly what the scenario requires. sudo (A) is only a privilege-delegation tool for running commands as another user and does not enforce MAC confinement. TCP wrappers (D) provide host-based access control for network services via hosts.allow/hosts.deny, not mandatory access control. iptables (E) is a packet-filtering firewall that controls network traffic, not process-level mandatory access control.

Answer

sudo

Answer

TCP wrappers

Answer

iptables

Question 5

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?

Accepted Answer

YAML files that declare the desired state of systems and tasks to achieve it.. Ansible playbooks are YAML files that declare the desired state of systems and the tasks to achieve that state, making them the core configuration management tool in Ansible. They are idempotent, meaning running them multiple times yields the same result, and they use modules to enforce configurations without requiring an agent on managed nodes.

Answer

Executable scripts written in Python that run on managed nodes.

Answer

Configuration files that list the inventory of managed hosts.

Answer

Shell scripts that execute ad-hoc commands across servers.

Question 6

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

Accepted Answer

It causes the script to exit if any command fails.. set -e causes the script to exit immediately if any command exits with a non-zero status. This is useful for catching errors early.

Answer

It enables debugging by printing commands and their arguments as they are executed.

Answer

It prevents the script from overwriting existing files.

Answer

It treats unset variables as an error and exits.

Question 7

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?

Accepted Answer

[[ -r file ]]. The -e test checks if a file exists, and -r checks if it is readable. Using -f also checks for a regular file, but the question requires existence and readability, so combining -e and -r is correct. However, the options include -f and -r, but -f alone does not check readability. The correct combination is -e and -r, but since that is not an option, the best answer is -r because it implies existence? Actually, -r returns true only if the file exists and is readable. So -r alone satisfies both conditions.

Answer

[[ -e file ]]

Answer

[[ -f file ]]

Answer

[[ -s file ]]

Question 8

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

Accepted Answer

spec.replicas. In a Deployment spec, the 'replicas' field sets the desired number of pod instances.

Answer

metadata.replicas

Answer

spec.template.replicas

Answer

spec.containers.replicas

Question 9

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

Accepted Answer

It specifies the path to the Bash executable that should run the script.. The shebang tells the system which interpreter to use to execute the script.

Answer

It defines a variable for the Bash version.

Answer

It sets the script's permissions to executable.

Answer

It enables debug mode for the script.

Question 10

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?

Accepted Answer

lineinfile. The lineinfile module ensures a specific line is present in a file, ideal for configuration management.

Answer

template

Answer

shell

Answer

copy