CompTIA Linux+ Certification Exam XK0-004 Dumps V13.02

1. A Linux systems administrator is setting up SSH access with PKI for several using their newly created RSA keys .

Which of the following MOST securely achieves this task?

2. A systems administrator receives a report that the web server is not running after a planned system reboot.

After starting the web server manually, which of the following commands should the administrator issue to ensure the web server starts at boot time?

3. A user wants to alias dir so it always returns the contents of the ls -la command. However, the user has to reset the alias with every login.

Which of the following is the BEST action the user can take to ensure the command is always available?

4. A Linux systems administrator needs to set permissions on an application with the following parameters:

The owner of the application should be able to read, write, and execute the application.

Members of the group should be able to read and execute the application.

Everyone else should not have access to the application.

Which of the following commands would BEST accomplish these tasks?

5. An administrator needs to kill the oldest Bash shell running in the system .

Which of the following commands should be issued to accomplish this task?

6. A Linux team is using Git to version a set of custom scripts. A team member has made an update to a script and published the changes to the repository.

Which of the following is the BEST way to retrieve the latest changes to the administrator's local working copy?

7. A technician wants to secure a sensitive workstation by ensuring network traffic is kept within the local subnet.

To accomplish this task, the technician executes the following command:

echo 0 > /proc/sys/net/ipv4/ip_default_ttl

Which of the following commands can the technician use to confirm the expected results? (Choose two.)

8. A junior systems administrator is scanning archive.tar files with an antivirus scanner.

The administrator is given the following tasks:

✑ List all files that are in the archive.tar files.

✑ Extract all files from the archive.tar files.

Which of the following actions should be performed to meet these requirements? (Choose two.)

9. A Linux administrator needs to disable the Sendmail service on a Linux server and prevent it from being started manually and during boot.

Which of the following is the BEST command to do this?

10. A junior Linux administrator is installing patches using YUM.

The administrator issues the following command:

yum list installed

The output of the command is as follows:

Given this scenario and the output, which of the following should the administrator do to address this issue?

11. A Linux systems administrator wants the ability to access systems remotely over SSH using RSA authentication. to which of the following files should the RSA token be added to allow this access?

12. In order to comply with new security policies, an administrator needs to prevent the SSH server from using insecure algorithms.

Which of the following files should be edited to accomplish this?

13. A new IO card has been added to the security server to log the opening and closing of the main entrance. A switch is attached, so the interface card returns a 1 when the door is opened and a 0 when the door is closed.

Which of the following describes the Linux device to which this switch is attached?

14. A user wants to use terminal services from a Windows workstation to manage a Linux server .

Which of the following should be installed on the Linux server to enable this functionality?

15. A Linux administrator wants to configure log messages of critical or higher severity levels from the cron utility to be logged to the console .

Which of the following will accomplish this objective?

16. A Linux administrator is restoring the SELinux contexts on an entire system .

Which of the following commands is the BEST option to complete this task?

17. Which of the following are classified as Linux GUI servers? (Choose two.)

18. A Linux administrator is using a public cloud provider to host servers for a company’s website. Using the provider’s tools, the administrator wrote a JSON file to define how to deploy the servers .

Which of the following techniques did the administrator use?

19. A Linux administrator wants to fetch a Git repository from a remote Git server.

Which of the following is the BEST command to perform this task?

20. A new user has been added to a Linux machine .

Which of the following directories would contain the user’s

default files?

21. An issue was discovered on a testing branch of a Git repository. A file was inadvertently modified and needs to be reverted to the master branch version .

Which of the following is the BEST option to resolve the issue?

22. Users are unable to connect to a server using HTTPS.

The administrator runs the following command on the remote system:

Then, the administrator runs the following command from a local workstation:

Which of the following steps should the administrator take to address the issue?

23. An administrator reviews the following configuration file provided by a DevOps engineer:

Which of the following would the application parsing this file MOST likely have to support?

24. A junior systems administrator is diagnosing an issue with latency.

The administrator issues the command mtr www.comptia.org at a terminal and receives the following output:

Given this scenario and the output, which of the following should be reported to the network team for investigation? (Choose two.)

25. Given that a company’s policy states that users cannot install third-party tools on Window servers, which of the following protocols will allow a Linux GUI to connect to a Windows server?

26. Which of the following boot methods can a Linux administrator use to boot a Linux server remotely via a network interface card instead of a local disk?

27. A systems administrator manually added a new library to the server. The administrator wants to rebuild the library cache for immediate use.

Which of the following commands should the systems administrator run to achieve this goal?

28. A new video card was added to a customer workstation. To get the new video card to work correctly, a systems administrator needs to remove support for the nouveau video driver on the Linux workstation.

Which of the following will accomplish this task?

29. A user has been locked out of an account due to too many failed password attempts .

Which of the following commands will unlock the user’s account?

30. In which of the following directories is the vmlinuz file located?

31. A Linux administrator suspects unauthorized users are attempting to log in to the Linux server remotely .

Which of the following should the administrator check FIRST?

32. An administrator needs a bootable USB for installing a new Linux machine. The administrator downloaded the image file and named it as Linux_OS.iso in the /tmp directory .

Which of the following commands will accomplish that task?

33. Which of the following will provide a list of all flash, external, internal, and SSD drives?

34. All users are reporting that they cannot connect to the SFTP server.

The administrator runs a scan:

Which of the following would allow the administrator to fix the problem?

35. A systems administrator is receiving errors while trying to install a popular virtualization software. The software specifications state the processor needs to support virtualization with Intel instructions. Additional requirements state the processor must accelerate encryption/decryption and use hyperthreading.

Given the following output about the processor:

fpu ume depse tsu msr pae mce cx8 apic sep mtrr pae mca cmov pat pse36 cflusm mmx

fxsr sse sse2 ht syscall nx rdtscp lm constant_tsc rep_good nopl xtopology

nonstop_tsc pni pclmulqdq ssse3 cx16 pcid sse4_1 sse4_2 x2apic popcnt aes xsave

avx rdrand hypervisor lahf_lm fsgsbase

Which of the following is the MOST likely reason for the errors?

36. A systems administrator observes high latency values when reaching a remote web server .

Which of the following commands will help determine and isolate issues on the network side?

37. Joe, a user, reports that he is no longer able to write files to his home directory. Upon inspection, the Linux administrator discovers that attempting to create a new file gives the following error: No space left on device. However, the disk and partition are not full .

Which of the following commands would be BEST for the administrator to use to continue troubleshooting this problem?

38. A raw VM image is being compressed with bzip2 and copied to a flash drive at /dev/hdb for off-site use by the marketing department .

Which of the following command lines accomplishes this task?

39. Which of the following are Linux desktop managers? (Choose two.)

40. A Linux administrator tried to copy files to a remote server but received an error message indicating a lack of free space on the disk. The administrator issued a df command and verified adequate free space and inodes on the filesystem.

Which of the following commands is the BEST way to diagnose the issue?

41. A Linux administrator needs to prevent the Postfix mail transfer agent from starting on boot.

Which of the following commands will accomplish this task?

42. A user attempts to use the mount -a command but gets the following error:

mount: mount point /mnt/test does not exist

Which of the following commands best describes the action the Linux administrator should take NEXT?

43. An administrator needs to generate a list of services that are listening on TCP and/or UDP ports .

Which of the following tools should the administrator use?

44. A systems administrator needs to run the yum update command two hours after employees log off and leave for the day on Friday.

Which of the following is the BEST command to complete the task, if the task only needs to be run once?

45. A user issues the following command:

ls Cl /var/log | egrep Ce ‘^d[rwx]{3}.*[rw-]{3}.*’

The list of files in the system is shown below:

Which of the following results matches the command issued?

46. An administrator needs to change the DNS domain search order of a single Linux host to localize it better.

Which of the following files should the administrator edit?

47. A company wants to provide internal identity verification services for networked devices .

Which of the following servers should be installed?

48. A Linux administrator attempts to install the package newprogram.x86_64.rpm using a package manager.

The administrator receives a warning indicating the command that was run was using a deprecated package manager .

Which of the following commands should the administrator use to avoid the warning and install the newprogram.x86_64.rpm program?

49. A Linux administrator has installed a web application firewall in front of a web server running on HTTP port 8080 and successfully started the HTTP server. However, after opening the application URL in an Internet browser, the administrator discovered that the application does not work.

The administrator performed the following diagnostic steps:

Output of sysctl -a command:

Output of iptables -L command:

Output of netstat Cnltop | grep "8080":

Which of the following is the NEXT step the administrator should perform to permanently fix the issue at the kernel level?

50. An administrator receives an alarm because the disk of one of the sewers is running out of space .

Which of the following commands can be used to see the space that each partition is using?

51. A file server is sharing a directory called /share between team members inside a company. The fileshare needs to be moved from serverA to /newshare located on serverB with all permissions and attributes preserved .

Which of the following commands would BEST achieve this task?

52. A junior systems administrator is tasked with providing the network_administrators group the ability to

perform sudo without prompting for a password .

Which of the following steps should the administrator perform to accomplish this task? (Choose two.)

53. A Linux administrator wants to obtain a list of files and subdirectories in the /etc directory that contain the word “services”. Once the files and subdirectories are discovered, they should be listed alphabetically in the /var/tmp/foundservices file .

Which of the following shell scripts will accomplish this task?

54. A Linux systems administrator installed a new web server, which failed while attempting to start. The administrator suspects that SELinux is causing an issue and wants to temporarily put the system into permissive mode .

Which of the following would allow the administrator to accomplish this?

55. A technician suspects a company's border firewall is down, thus blocking Internet access.

The technician executes the following commands:

#ping -c 1 firewall.company.com

64 bytes from firewall.company.com (192.168.1.1): icmp_seq=1 ttl=64 time=0.061ms

#ping -c 16 www.comptia.com

16 packets transmitted, 0 received, 100% packet loss, time 14999ms

Which of the following commands should the technician use to BEST determine the source of this outage?

56. An administrator notices that a long-running script, /home/user/script.sh, is taking up a large number of system resources. The administrator does not know the script’s function .

Which of the following commands should the administrator use to minimize the script’s impact on system resources?

57. An engineer is working on a production application deployment that requires changing a web application property file called server.property that is managed by the Git version control system. A cloned copy of the remote repository in which the server.property file exists is on the local desktop computer. The engineer makes appropriate changes to the files, saves it as server.property, and executes git commit Cm “changed the property file” server.property .

Which of the following commands did the engineer fail to perform?

58. Joe, a user, is unable to log in to the server and contracts the systems administrator to look into the issue.

The administrator examines the /etc/passwd file and discovers the following entry:

joe:x:505:505::/home/joe:/bin/false

Which of the following commands should the administrator execute to resolve the problem?

59. A Linux systems administrator is troubleshooting an issue with the /home directory running out of space. The administrator needs to determine which /home directories are using the most space .

Which of the following commands should be used?

60. A Linux administrator needs every new file created on a directory to maintain the group permissions of the same directory .

Which of the following commands would satisfy this requirement?

61. Which of the following servers provides encrypted tunnel SOCKS services?

62. A Linux administrator is updating iptables rules and is given the following tasks:

✑ Output a list of iptables rules.

✑ Remove all iptables rules.

Which of the following actions should be performed from the terminal console to accomplish these tasks?

(Choose two.)

63. A Linux administrator tries to ping a hostname in a network but receives the message: hostname not found. The administrator is sure the name exists on the network and wants to verify if the DNS server is correctly configured on the client .

Which of the following files should the administrator use to verify this information?

64. A user wants to list the lines of a log, adding a correlative number at the beginning of each line separated by a set of dashes from the actual message .

Which of the following scripts will complete this task?

A)

B)

C)

D)

65. A junior Linux administrator is trying to verify connectivity to the remote host host1 and display round-trip statistics for ten ICMP.

Which of the following commands should the administrator execute?

66. A Linux system is running normally when the systems administrator receives an alert that one application spawned many processes. The application is consuming a lot of memory, and it will soon cause the machine to become unresponsive .

Which of the following commands will stop each application process?

67. Which of the following BEST describes the purpose of the X11 system?

68. An administrator needs to deploy 100 identical CentOS workstations via PXE boot .

Which of the following should the administrator use to minimize the amount of interaction with the consoles needed?

69. A Linux server has multiple IPs. A Linux administrator needs to verify if the HTTP server port is bound to the correct IP.

Which of the following commands would BEST accomplish this task?

70. A user needs to modify the IP address of a laptop .

Which of the following files can be used to configure the network interface named eth0?

71. Which of the following can be used to boot a DVD from a remote device to initialize a Linux system setup on bare metal hardware as if it is a local DVD?

72. A technician wants to secure a sensitive workstation by ensuring network traffic is kept within the local subnet.

To accomplish this task, the technician executes the following command:

echo 0 > /proc/sys/net/ipv4/ip_default_ttl

Which of the following commands can the technician use to confirm the expected results? (Choose two.)

73. A Linux systems administrator needs to provision multiple web servers into separate regional datacenters. The systems architect has instructed the administrator to define the server infrastructure using a specific tool that consumes a text-based file.

Which of the following is the BEST reason to do this?

74. A systems administrator needs to conduct maintenance on a server.

Which of the following commands will place the administrator in the appropriate runlevel?

75. A Linux administrator recently reprovisioned a new corporate web server to replace a legacy one. To minimize the impact on the company's users, the administrator modified the network and DNS settings of the new server to be the same as the legacy server.

When attempting to log in to the new server remotely over SSH, the following error message is displayed:

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

Which of the following should the administrator do to resolve the issue?

76. A junior systems administrator created a new filesystem /dev/sda1 with mountpoint /data and added it to the /etc/fstab for auto-mounting.

When the systems administrator tries to mount the file system, the system refuses.

Given the output below:

Which of the following steps is necessary?

77. On a UEFI-based system, which of the following invokes GRUB2 from the EFI command prompt?

78. When requesting SSH access to a remote system, a user accidentally emailed the id_rsa key to the administrator .

Which of the following should the user do NEXT?

79. A systems administrator wants to deploy several applications to the same server quickly. Each application should be abstracted from the host with its own dependencies and libraries and utilize a minimal footprint.

Which of the following would be BEST in this scenario?

80. An administrator is installing a new kernel but is getting an error indicating the filesystem is out of space. A disk usage check shows / has plenty of space.

Which of the following BEST represents where the administrator should check next?