CompTIA CompTIA Certifications XK0-004 Questions & Answers

• Question 131:

  A Linux engineer is troubleshooting a newly added SCSI device for a Linux server that needed more disk space without rebooting. The engineer discovers that the new device is not visible by the Linux kernel in fdisk -l output. Which of the following commands should be used to rescan the entire SCSI bus?

  A. echo "- - -" > /sys/class/scsi_host/host0/scan

  B. echo ' ' > /sys/class/scsi_host/host0/scan

  C. echo "- - -" > /sys/scsi/scsi_host/host0/scan

  D. echo "scan" > /sys/class/scsi_host/host0/scan

  Correct Answer: A

  Reference: https://geekpeek.net/rescan-scsi-bus-on-linux-system/

• Question 132:

  Ann, a user, has created a new directory and noticed that permissions on the new directory are as follows:

  drwx------. 1 ann ann 0 Jun 11 08:20 work

  Which of the following should the administrator do to restore default permissions for newly created directories?

  A. Change umask value in /etc/profile.

  B. Run chmod command to update permissions.

  C. Modify directory ownership to ann:ann with chown.

  D. Execute chattr command to restore default access.

  Correct Answer: A

  Reference: https://geek-university.com/linux/set-the-default-permissions-for-newly-created-files/

• Question 133:

  An administrator received a request from a security officer to eliminate a blacklisting set called internal-blocked the company is using in the iptables firewall. Which of the following commands will complete the task?

  A. ipset swap internal-blocked none

  B. ipset destroy internal-blocked

  C. ipset del internal-blocked

  D. ipset remove internal-blocked

  Correct Answer: B

• Question 134:

  Which of the following will boot from a network-hosted ISO image at power on?

  A. PXE

  B. FTP

  C. iSCSI

  D. NFS

  Correct Answer: A

• Question 135:

  A systems administrator is editing a service file for the web server. In order to continue testing, all web server processes must be shut down. The administrator accomplishes this with the following commands:

  

  Based on the command output above, which of the following BEST explains how this was accomplished?

  A. Killing the parent process with -15 gives it a chance to kill all of the child processes.

  B. The -15 signal will allow the kill command to automatically seek out all child processes and kill them as well.

  C. The -15 signal tells the kill command to kill all processes matching the Apache string.

  D. The -15 signal gracefully kills the process and all Its parent and child processes.

  Correct Answer: A

• Question 136:

  A Linux administrator needs to know the MAC address of the server's gateway.

  Which of the following commands should the administrator run to obtain this information?

  A. arp -gw

  B. arp -a

  C. arp -gwi

  D. arp -gtw

  Correct Answer: B

• Question 137:

  A systems administrator is investigating low performance a server. After executing some diagnostic commands, the administrator analyzes the data: Which of the following is the cause of low performance on the server?

  

  A. Lack of swap space

  B. Lack of available memory

  C. User processes have taken up all the available CPU time

  D. High disk activity

  Correct Answer: C

• Question 138:

  A security team informs the Linux administrator that a specific server is acting as an open relay. To which of the following is the security team referring?

  A. The server is running the SSH service and is open to the Internet, allowing outside sources to log into the server without source IP address filtering.

  B. The server is acting as an unmanaged router, open to the Internet, and is allowing outside Internet traffic into the network with no filtering.

  C. The server is acting as a web proxy and allowing outside unauthenticated sources to connect to the server, effectively hiding the source's IP address for malicious activities.

  D. The server has an email service configured to allow outside sources to send email to other external parties on the Internet without validation.

  Correct Answer: D

• Question 139:

  A systems administrator needs to install software packages on a server from an Internet-based repository. The server does not have Internet connectivity. Which of the following can be used to allow the server to connect to the Internet through the systems administrator's desktop?

  A. Local package repository

  B. UUCP

  C. Remote SSH port forwarding

  D. X11 forwarding

  Correct Answer: C

• Question 140:

  An administrator needs to set the time of a VM that has no network connectivity to an NTP server. The VM's host, however, is synchronized with NTP. Which of the following allows the administrator to synchronize the time of the VM with the host?

  A. time

  B. date

  C. hwclock

  D. ntpdate

  Correct Answer: C