CompTIA XK0-005 Online Practice Questions and Exam Preparation

CompTIA XK0-005 Online Questions & Answers

• Question 141:

  A Linux administrator is creating a new sudo profile for the accounting user. Which of the following should be added by the administrator to the sudo configuration file so that the accounting user can run / opt/ acc/ report as root?

  A. accounting localhost=/opt/acc/report
  B. accounting ALL=/opt/acc/report
  C. %accounting ALL=(ALL) NOPASSWD: /opt/acc/report
  D. accounting /opt/acc/report= (ALL) NOPASSWD: ALL
  C. %accounting ALL=(ALL) NOPASSWD: /opt/acc/report

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  Explanation

  This answer allows the accounting user to run the /opt/acc/report command as root on any host without entering a password. The % sign indicates that accounting is a group name, not a user name. The ALL keyword means any host, any user, and any command, depending on the context. The NOPASSWD tag overrides the default behavior of sudo, which is to ask for the user's password.

  The other answers are incorrect for the following reasons:

  A. accounting localhost=/opt/acc/report

  B. accounting ALL=/opt/acc/report

  D. accounting /opt/acc/report= (ALL) NOPASSWD: ALL

• Question 142:

  A Linux administrator is reviewing changes to a configuration file that includes the following section: The Linux administrator is trying to select the appropriate syntax formatter to correct any issues with the configuration file. Which of the following should the syntax formatter support to meet this goal?

  

  A. Markdown
  B. XML
  C. YAML
  D. JSON
  C. YAML

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  Explanation

  The configuration file shown in the image is written in YAML format, so the syntax formatter should support YAML to correct any issues with the file. YAML stands for YAML Ain't Markup Language, and it is a human-readable data serialization language that uses indentation and colons to define key-value pairs. YAML supports various data types, such as scalars, sequences, mappings, anchors, aliases, and tags. The configuration file follows the rules and syntax of YAML, while the other options do not. Markdown is a lightweight markup language that uses plain text formatting to create rich text documents. XML is a markup language that uses tags to enclose elements and attributes. JSON is a data interchange format that uses curly braces to enclose objects and square brackets to enclose arrays.

  References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 21: Automating Tasks with Ansible, page 591.

• Question 143:

  Users are reporting that a Linux server is responding slowly. A systems administrator troubleshooting the server issue sees the following iostat output, with %iowait at 50.38. Which of the following is most likely the issue?

  A. The CPU is mostly waiting for I/O operations.
  B. / filesystem does not have enough storage allocated.
  C. /var filesystem is almost full.
  D. The CPU capacity is inadequate.
  A. The CPU is mostly waiting for I/O operations.

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  Explanation

  The %iowait value represents the percentage of time the CPU is waiting for I/O operations to complete. A high %iowait value suggests the system is bottlenecked by disk I/O, which could lead to slow response times. Addressing disk I/O bottlenecks would improve performance.

  Linux Performance Monitoring with iostat

• Question 144:

  After installing a new version of a package, a systems administrator notices a new version of the corresponding, service file was Installed In order to use the new version of the, service file, which of the following commands must be Issued FIRST?

  A. systemct1 status
  B. systemct1 stop
  C. systemct1 reinstall
  D. systemct1 daemon-reload
  D. systemct1 daemon-reload

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  Explanation

  After installing a new version of a package that includes a new version of the corresponding service file, the systemct1 daemon-reload command must be issued first in order to use the new version of the service file. This command will reload the systemd manager configuration and read all unit files that have changed on disk. This will ensure that systemd recognizes the new service file and applies its settings correctly. The systemct1 status command will display information about a service unit, but it will not reload the configuration. The systemct1 stop command will stop a service unit, but it will not reload the configuration. The systemct1 reinstall command does not exist.

  References: CompTIA Linux+ (XK0-005)

  Certification Study Guide, Chapter 17:

  System Maintenance and Operation, page 518.

• Question 145:

  A Linux administrator wants to set the SUID of a file named dev_team.text with 744 access rights. Which of the following commands will achieve this goal?

  A. chmod 4744 dev_team.txt
  B. chmod 744 --setuid dev_team.txt
  C. chmod -c 744 dev_team.txt
  D. chmod -v 4744 --suid dev_team.txt
  A. chmod 4744 dev_team.txt

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  Explanation

  The command that will set the SUID of a file named dev_team.txt with 744 access rights is chmod 4744 dev_team.txt. This command will use the chmod utility to change the file mode bits of dev_team.txt. The first digit (4) represents the SUID bit, which means that when someone executes dev_team.txt, it will run with the permissions of the file owner. The next three digits (744) represent the read, write, and execute permissions for the owner (7), group (4), and others (4). This means that the owner can read, write, and execute dev_team.txt, while the group and others can only read it. The other options are not correct commands for setting the SUID of a file with 744 access rights. The chmod 744 --setuid dev_team.txt command is invalid because there is no -- setuid option in chmod. The chmod -c 744 dev_team.txt command will change the file mode bits to 744, but it will not set the SUID bit. The -c option only means that chmod will report when a change is made. The chmod -v 4744 --suid dev_team.txt command is also invalid because there is no --suid option in chmod. The -v option only means that chmod will output a diagnostic for every file processed.

  References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 8: Managing Users and Groups; chmod(1) - Linux manual page

• Question 146:

  A Linux administrator has defined a systemd script docker-repository.mount to mount a volume for use by the Docker service. The administrator wants to ensure that Docker service does not start until the volume is mounted. Which of the following configurations needs to be added to the Docker service definition to best accomplish this task?

  A. After=docker-respository.mount
  B. ExecStart=/usr/bin/mount -a
  C. Requires=docker-repository.mount
  D. RequiresMountsFor=docker-repository.mount
  C. Requires=docker-repository.mount

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  Explanation

  This option declares an explicit dependency between the Docker service and the docker- repository.mount unit. It means that the Docker service will not start unless the docker- repository.mount unit is successfully activated. This ensures that the volume is mounted before the Docker service tries to use it12.

  References: 1: systemd.unit - systemd unit configuration 2: How to mount host volumes into docker containers in Dockerfile during build

• Question 147:

  Which of the following commands is used to tune kernel parameters?

  A. sysctl
  B. ss
  C. mkinitrd
  D. lsof
  A. sysctl

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  Explanation

  sysctl is used to modify kernel parameters at runtime. It is used for setting system settings related to networking, memory management, and other kernel options. These settings are stored in /etc/sysctl.conf for persistence across reboots.

• Question 148:

  DRAG DROP

  As a Systems Administrator, to reduce disk space, you were tasked to create a shell script that does the following:

  Add relevant content to /tmp/script.sh, so that it finds and compresses rotated files in /var/log without recursion.

  INSTRUCTIONS

  Fill the blanks to build a script that performs the actual compression of rotated log files.

  If at any time you would like to bring back the initial state of the simulation, please click the Reset All button.

  Select and Place:

  

  

• Question 149:

  A Linux engineer is removing a previously created firewall rule.

  Which of the following commands will help the administrator accomplish this task?

  A. ufw delete 80/tcp
  B. ufw delete deny 80/tcp
  C. ufw delete 80/tcp deny
  D. delete7!
  B. ufw delete deny 80/tcp

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  Explanation

  The ufw (Uncomplicated Firewall) delete command is used to remove rules. If the original rule was ufw deny 80/tcp, it must be deleted with:ufw delete deny 80/tcp

• Question 150:

  A systems administrator needs to disable root login for SSH. Which of the following commands should the administrator use?

  A. touch /etc/ssh/sshd_config | awk 's/PermitRootLoginX yes/PermitRootLoginX no/'
  B. sed -i 's/PermitRootLogin yes/PermitRootLogin no/' /etc/ssh/sshd_config
  C. touch /etc/ssh/sshd_config | print* 1PermitRootLogin/PermitRootLogin no/'
  D. cat /etc/ssh/sshd_config | grep 's/PermitRootLogin yes/PermitRootLogin no/'
  B. sed -i 's/PermitRootLogin yes/PermitRootLogin no/' /etc/ssh/sshd_config

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  Explanation