CompTIA XK0-005 Online Practice Questions and Exam Preparation

CompTIA XK0-005 Online Questions & Answers

• Question 281:

  Which of the following would significantly help to reduce data loss if more than one drive fails at the same time?

  A. Server clustering
  B. Load balancing
  C. RAID
  D. VDI
  C. RAID

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  Explanation

  RAID stands for Redundant Array of Independent Disks, which is a technology that combines multiple physical disks into a logical unit that provides improved performance, reliability, or both. RAID can significantly help to reduce data loss if more than one drive fails at the same time, depending on the RAID level used. For example, RAID 1 (mirroring) duplicates the data on two or more disks, so that if one disk fails, the data can be recovered from another disk. RAID 5 (striping with parity) distributes the data and parity information across three or more disks, so that if one disk fails, the data can be reconstructed from the remaining disks. RAID 6 (striping with double parity) extends RAID 5 by adding another parity block, so that if two disks fail, the data can still be recovered from the remaining disks.

  References: [What is RAID?]

• Question 282:

  A Linux administrator wants to prevent the httpd web service from being started both manually and automatically on a server. Which of the following should the administrator use to accomplish this task?

  A. systemctl mask httpd
  B. systemctl disable httpd
  C. systemctl stop httpd
  D. systemctl reload httpd
  A. systemctl mask httpd

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  Explanation

  The best command to use to prevent the httpd web service from being started both manually and automatically on a server is A. systemctl mask httpd. This command will create a symbolic link from the httpd service unit file to /dev/null, which will make the service impossible to start or enable. This is different from systemctl disable httpd, which will only prevent the service from starting automatically on boot, but not manually. The other commands are either not relevant or not sufficient for this task. For example:

  C. systemctl stop httpd will only stop the service if it is currently running, but it will not prevent it from being started again.

  D. systemctl reload httpd will only reload the configuration files of the service, but it will not stop or disable it.

• Question 283:

  A junior administrator is setting up a new Linux server that is intended to be used as a router at a remote site. Which of the following parameters will accomplish this goal?

  

  A. Option A
  B. Option B
  C. Option C
  D. Option D
  C. Option C

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  Explanation

  The parameter net.ipv4.ip_forward=1 will accomplish the goal of setting up a new Linux server as a router. This parameter enables the IP forwarding feature, which allows the server to forward packets between different network interfaces. This is necessary for a router to route traffic between different networks. The parameter can be set in the /etc/sysctl.conf file or by using the sysctl command. This is the correct parameter to use to accomplish the goal. The other options are incorrect because they either do not exist (net.ipv4.ip_forwarding or net.ipv4.ip_route) or do not enable IP forwarding (net.ipv4.ip_forward=0).

  References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 12: Managing Network Connections, page 382.

• Question 284:

  A systems administrator is investigating why one of the servers has stopped connecting to the internet.

  

  Which of the following is causing the issue?

  A. The DNS address has been commented out in the configuration file.
  B. The search entry in the /etc/resolv.conf file is incorrect.
  C. Wired connection 1 is offline.
  D. No default route is defined.
  D. No default route is defined.

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  Explanation

  The issue is caused by the lack of a default route defined in the /etc/sysconfig/network-scripts/ifcfg-enp0s3 file. A default route is a special route that specifies where to send packets that do not match any other routes in the routing table. Without a default route, the server will not be able to communicate with hosts outside its local network. The default route is usually configured with the GATEWAY option in the network interface configuration file. For example, to set the default gateway to 192.168.1.1, the file should contain: GATEWAY=192.168.1.1 The other options are not causing the issue. The DNS address is not commented out in the configuration file, it is specified with the DNS1 option. The search entry in the /etc/resolv.conf file is correct, it specifies the domain name to append to unqualified hostnames. Wired connection 1 is online, as indicated by the ONBOOT=yes option and the output of ip link show enp0s3 command.

  References: Configuring IP Networking with nmcli; Configuring IP Networking with ifcfg Files

• Question 285:

  A systems administrator is troubleshooting connectivity issues and trying to find out why a Linux server is not able to reach other servers on the same subnet it is connected to. When listing link parameters, the following is presented:

  

  Based on the output above, which of following is the MOST probable cause of the issue?

  A. The address ac:00:11:22:33:cd is not a valid Ethernet address.
  B. The Ethernet broadcast address should be ac:00:11:22:33:ff instead.
  C. The network interface eth0 is using an old kernel module.
  D. The network interface cable is not connected to a switch.
  D. The network interface cable is not connected to a switch.

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  Explanation

  The most probable cause of the connectivity issue is that the network interface cable is not connected to a switch. This can be inferred from the output of the ip link list dev eth0 command, which shows that the network interface eth0 has the NO- CARRIER flag set. This flag indicates that there is no physical link detected on the interface, meaning that the cable is either unplugged or faulty. The other options are not valid causes of the issue. The address ac:00:11:22:33:cd is a valid Ethernet address, as it follows the format of six hexadecimal octets separated by colons. The Ethernet broadcast address should be ff:ff:ff:ff:ff:ff, which is the default value for all interfaces. The network interface eth0 is not using an old kernel module, as it shows the UP flag, which indicates that the interface is enabled and ready to transmit data.

  References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 14: Managing Networking

• Question 286:

  An administrator set up a new user account called "test". However, the user is unable to change their password. Given the following output: Which of the following is the most likely cause of this issue?

  

  A. The SUID bit is missing on the /bin/passwd file.
  B. The password provided by the user "test" does not meet complexity requirements.
  C. The user "test" already changed the password today.
  D. The password has been disabled for user "test".
  A. The SUID bit is missing on the /bin/passwd file.

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  Explanation

• Question 287:

  A systems administrator checked out the code from the repository, created a new branch, made changes to the code, and then updated the main branch. The systems administrator wants to ensure that the Terraform state files do not appear in the main branch. Which of following should the administrator use to meet this requirement?

  A. clone
  B. gitxgnore
  C. get
  D. .ssh
  B. gitxgnore

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  Explanation

  To prevent certain files from being tracked by Git, the administrator can use a .gitignore file (B) in the repository. The .gitignore file can specify patterns of files or directories that Git should ignore. This way, the Terraform state files will not appear in the main branch or any other branch. The other commands are not related to this requirement.

  References:

  [CompTIA Linux+ Study Guide], Chapter 10: Working with Git, Section: Ignoring Files with .gitignore

  [How to Use .gitignore File]

• Question 288:

  A Linux administrator cloned an existing Linux server and built a new server from that clone. The administrator encountered the following error after booting the cloned server:

  

  The administrator performed the commands listed below to further troubleshoot and mount the missing filesystem:

  

  Which of the following should administrator use to resolve the device mismatch issue and mount the disk?

  A. mount disk by device-id
  B. fsck -A
  C. mount disk by-label
  D. mount disk by-blkid
  A. mount disk by device-id

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  Explanation

  The administrator should use the command mount disk by device-id to resolve the device mismatch issue and mount the disk. The issue is caused by the cloned server having a different device name for the disk than the original server. The output of blkid shows that the disk has the device name /dev/sdb1 on the cloned server, but the output of cat /etc/fstab shows that the disk is expected to have the device name /dev/sda1. The command mount disk by device-id will mount the disk by using its unique identifier (UUID) instead of its device name. The UUID can be obtained from the output of blkid or lsblk -f. The command will mount the disk to the specified mount point (/data) and resolve the issue. The other options are incorrect because they either do not mount the disk (fsck -A), do not use the correct identifier (mount disk by-label or mount disk by-blkid), or do not exist (mount disk by-blkid).

  References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 10: Managing Storage, pages 318-319.

• Question 289:

  A systems administrator is investigating an issue in which one of the servers is not booting up properly. The journalctl entries show the following:

  

  Which of the following will allow the administrator to boot the Linux system to normal mode quickly?

  A. Comment out the /opt/app filesystem in /etc/fstab and reboot.
  B. Reformat the /opt/app filesystem and reboot.
  C. Perform filesystem checks on local filesystems and reboot.
  D. Trigger a filesystem relabel and reboot.
  A. Comment out the /opt/app filesystem in /etc/fstab and reboot.

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  Explanation

  The fastest way to boot the Linux system to normal mode is to comment out the /opt/app filesystem in /etc/fstab and reboot. This will prevent the system from trying to mount the /opt/app filesystem at boot time, which causes an error because the filesystem does not exist or is corrupted. Commenting out a line in /etc/fstab can be done by adding a # symbol at the beginning of the line. Rebooting the system will apply the changes and allow the system to boot normally. Reformatting the /opt/app filesystem will not help to boot the system, as it will erase any data on the filesystem and require manual intervention to create a new filesystem. Performing filesystem checks on local filesystems will not help to boot the system, as it will not fix the missing or corrupted /opt/app filesystem. Triggering a filesystem relabel will not help to boot the system, as it will only change the security context of files and directories according to SELinux policy.

  References: CompTIA Linux+ (XK0- 005) Certification Study Guide, Chapter 14: Managing Disk Storage, page 456.

• Question 290:

  Users have been unable to save documents to /home/tmp/temp and have been receiving the following error:

  Path not found

  A junior technician checks the locations and sees that /home/tmp/tempa was accidentally created instead of /home/tmp/temp.

  Which of the following commands should the technician use to fix this issue?

  A. cp /home/tmp/tempa /home/tmp/temp
  B. mv /home/tmp/tempa /home/tmp/temp
  C. cd /temp/tmp/tempa
  D. ls /home/tmp/tempa
  B. mv /home/tmp/tempa /home/tmp/temp

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  Explanation

  The mv /home/tmp/tempa /home/tmp/temp command will fix the issue of the misnamed directory. This command will rename the directory /home/tmp/tempa to /home/tmp/temp, which is the expected path for users to save their documents.

  The cp /home/tmp/tempa /home/tmp/temp command will not fix the issue, as it will copy the contents of /home/tmp/tempa to a new file named /home/tmp/temp, not a directory. The cd /temp/tmp/tempa command will not fix the issue, as it will

  change the current working directory to /temp/tmp/tempa, which does not exist. The ls /home/tmp/tempa command will not fix the issue, as it will list the contents of /home/tmp/tempa, not rename it.

  References: CompTIA Linux+ (XK0-005)

  Certification Study Guide, Chapter 12:

  Managing Files and Directories, page 413.