CompTIA XK0-006 Online Practice Questions and Exam Preparation

CompTIA XK0-006 Online Questions & Answers

• Question 101:

  A systems administrator is having issues with a third-party API endpoint. The administrator receives the following output:

  

  Which of the following actions should the administrator take to resolve the issue?

  A. Open a secure port in the server's firewall.
  B. Request a new API endpoint from a third party.
  C. Review and fix the DNS client configuration file.
  D. Enable internet connectivity on the host.
  C. Review and fix the DNS client configuration file.

  ---

  Explanation

  This scenario represents a name resolution failure , which is a common troubleshooting case addressed in CompTIA Linux+ V8. The critical clues are the error messages returned by both curl and dig.

  The curl error "Could not resolve host" indicates that the system is unable to translate the hostname into an IP address. This is confirmed by the dig output, which returns NXDOMAIN , meaning the DNS resolver cannot resolve the requested domain name. Importantly, the dig output shows that the query is reaching a DNS server (10.255.255.254), but the resolution fails, strongly pointing to a DNS client configuration issue .

  Option C , reviewing and fixing the DNS client configuration file (such as /etc/resolv.conf or systemd- resolved settings), is the correct action. Linux+ V8 documentation highlights DNS misconfiguration as a primary cause of application connectivity issues. Incorrect nameserver entries, unreachable DNS servers, or misconfigured resolvers commonly produce NXDOMAIN responses.

  The other options are incorrect. Firewall issues would result in connection timeouts, not DNS resolution failures. Requesting a new API endpoint is unnecessary without first confirming local DNS functionality. Internet connectivity issues would typically prevent any DNS communication, but here a DNS server is clearly being contacted.

  Linux+ V8 stresses a layered troubleshooting approach: verify DNS resolution before investigating network ports or application logic.

• Question 102:

  Which of the following best describes the function of Linux inodes?

  A. To manage a list of filesystem ACLs
  B. To store data using copy-on-write
  C. To store encrypted file data
  D. To track file metadata
  D. To track file metadata

• Question 103:

  A systems administrator engineer wants to configure a Linux server's time zone to America/Chicago. The engineer verifies that the server's time zone is configured for Asia/Tokyo:

  

  Which of the following commands should the engineer execute to make this change?

  A. date configure -set-timezone America/Chicago
  B. set-timezone -config America/Chicago
  C. time date set America/Chicago
  D. timedatect1 set-timezone America/Chicago
  D. timedatect1 set-timezone America/Chicago

• Question 104:

  A systems administrator receives reports of issues in one of the Linux systems. The following output has been provided:

  $ dig node.mycomptia.org

  ; <<>> DiG 9.11.36 <<>> node.mycomptia.org

  ;; global options: +cmd

  ;; connection timed out; no servers could be reached

  $ cat /etc/resolv.conf

  search mycomptia.org

  Which of the following actions will best resolve this issue? (Select two.)

  A. echo "8.8.8.8 node.mycomptia.org" >> /etc/hosts
  B. echo "nameserver 8.8.8.8" >> /run/systemd/resolve/resolv.conf
  C. systemctl restart networkd
  D. echo "nameserver 8.8.8.8" >> /etc/resolv.conf
  E. echo "DNS1=8.8.8.8" >> /etc/sysconfig/network-scripts/ifcfg-eth0
  F. systemctl restart NetworkManager
  G. systemctl restart named
  D. echo "nameserver 8.8.8.8" >> /etc/resolv.conf
  F. systemctl restart NetworkManager

• Question 105:

  A Linux systems administrator wants to validate the network interfaces configuration and status on a Linux server.

  Which of the following commands should the administrator use to display the information for interface eth3 including status, IP address, subnet mask, and configuration?

  A. ip list interface eth3
  B. ip addr show dev eth3
  C. ip show eth3
  D. ip config eth3
  B. ip addr show dev eth3

• Question 106:

  A Linux systems administrator is running an important maintenance task that consumes a large amount of CPU, causing other applications to slow.

  Which of the following actions should the administrator take to help alleviate the issue?

  A. Increase the available CPU time with pidstat.
  B. Lower the priority of the maintenance task with renice.
  C. Run the maintenance task with nohup.
  D. Execute the other applications with the bg utility.
  B. Lower the priority of the maintenance task with renice.

  ---

  Explanation

  Process scheduling and resource management are essential Linux administration skills covered in Linux+ V8. When a process consumes excessive CPU resources, it can negatively impact overall system performance.

  The correct solution is to lower the priority of the CPU-intensive task using the renice command. Niceness values influence how much CPU time a process receives relative to others. Increasing the niceness value reduces the process's priority, allowing other applications to receive CPU resources more fairly.

  Option B directly addresses the issue. The other options do not. pidstat monitors processes but does not modify CPU allocation. nohup allows a process to continue running after logout but does not affect scheduling priority. bg resumes a stopped job in the background but does not reduce CPU usage.

  Linux+ V8 documentation explicitly references nice and renice for managing CPU contention.

• Question 107:

  HOTSPOT

  A new drive was recently added to a Linux system. Using the environment and tokens provided, complete the following tasks:

  1. Create an appropriate device label.

  2. Format and create an ext4 file system on the new partition.

  The current working directory is /.

  

  

  ---

  To create an appropriate device label, format and create an ext4 file system on the new partition, you can use the following commands:

  To create a GPT (GUID Partition Table) label on the new drive /dev/sdc, you can use the parted command with the -s option (for script mode), the device name (/dev/sdc), the mklabel command, and the label type (gpt).

  The command is: parted -s /dev/sdc mklabel gpt

  To create a primary partition of 10 GB on the new drive /dev/sdc, you can use the parted command with the -s option, the device name (/dev/sdc), the mkpart command, the partition type (primary), the file system type (ext4), and the start and end points of the partition (1 and 10G).

  The command is: parted -s /dev/sdc mkpart primary ext4 1 10G

  To format and create an ext4 file system on the new partition /dev/sdc1, you can use the mkfs command with the file system type (ext4) and the device name (/dev/sdc1).

  The command is: mkfs.ext4 /dev/sdc1

  You can verify that the new partition and file system have been created by using the lsblk command, which will list all block devices and their properties.

• Question 108:

  A DevOps engineer made some changes to files in a local repository. The engineer realizes that the changes broke the application and the changes need to be reverted back.

  Which of the following commands is the best way to accomplish this task?

  A. git pull
  B. git reset
  C. git rebase
  D. git stash
  B. git reset

  ---

  Explanation

  Version control rollback operations are a core DevOps skill covered in the Linux+ V8 objectives. When changes in a local Git repository break an application and must be reverted, the administrator must choose a command that directly undoes those changes.

  The command git reset is the most appropriate option in this scenario. It allows the engineer to move the current branch pointer (HEAD) to a previous commit, effectively discarding or undoing local changes. Depending on the reset mode (--soft, --mixed, or --hard), the engineer can control whether changes are preserved in the staging area or working directory. This flexibility makes git reset the primary tool for reverting problematic local changes.

  The other options are not suitable. git pull fetches and merges changes from a remote repository and does not revert local modifications. git rebase rewrites commit history and is used to reapply commits on top of another base, not to undo broken changes. git stash temporarily saves uncommitted changes for later use but does not revert the repository to a stable state.

  Linux+ V8 documentation emphasizes that git reset is commonly used during local development when changes need to be undone quickly before being shared with others.

• Question 109:

  A Linux administrator needs to securely erase the contents of a hard disk.

  Which of the following commands is the best for this task?

  A. sudo rm -rf /dev/sda1
  B. sudo shred /dev/sda1
  C. sudo parted rm /dev/sda1
  D. sudo dd if=/dev/null of=/dev/sda1
  B. sudo shred /dev/sda1

  ---

  Explanation

  Secure data destruction is an important security requirement addressed in Linux+ V8 objectives. When data must be permanently erased, standard file deletion commands are insufficient because they do not overwrite the data on disk.

  The shred command is specifically designed to securely erase files or block devices by overwriting them multiple times with random data. Using sudo shred /dev/sda1 overwrites the entire partition, making data recovery extremely difficult or impossible. This aligns directly with Linux+ V8 best practices for secure data sanitization.

  The other options are incorrect. rm -rf removes directory entries but does not overwrite disk data. parted rm deletes partition entries but leaves the underlying data intact. dd if=/dev/null writes zero bytes and does not overwrite existing data blocks.

  Linux+ V8 documentation identifies shred as the most appropriate tool for secure erasure when compliance or confidentiality is required.

• Question 110:

  A systems administrator needs to validate that the dm_multipath driver was loaded in a Linux system.

  Which of the following commands should the administrator use?

  A. lsmod | grep dm_multipath
  B. modinfo | grep dm_multipath
  C. insmod | grep dm_multipath
  D. modprobe | grep dm_multipath
  A. lsmod | grep dm_multipath