CompTIA CompTIA Certifications XK0-004 Questions & Answers

• Question 341:

  An administrator is attempting to block SSH connections to 192.168.10.24 using the Linux firewall. After implementing a rule, a connection refused error is displayed when attempting to SSH to 192.168.10.24. Which of the following rules was MOST likely implemented?

  A. iptables -A -p tcp -d 192.168.10.24 --dport 22 -j REJECT

  B. iptables -A -p tcp -d 192.168.10.24 --dport 22 -j DROP

  C. iptables -A -p tcp -d 192.168.10.24 --dport 22 -j FORWARD

  D. iptables -A -p tcp -d 192.168.10.24 --dport 22 -j REFUSE

  Correct Answer: A

  Reference: https://www.golinuxhub.com/2014/03/how-to-allowblock-ssh-connection-from.html

• Question 342:

  A junior administrator needs to unload an older video kernel module. Which of the following commands would BEST accomplish this task?

  A. modprobe

  B. insmod

  C. rmmod

  D. chmod

  E. depmod

  Correct Answer: A

  Reference: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/ Kernel_Administration_Guide/sec-Unloading_a_Module.html

• Question 343:

  An administrator is analyzing a Linux server which was recently hacked.

  Which of the following will the administrator use to find all unsuccessful login attempts?

  A. nsswitch

  B. faillock

  C. pam_tally2

  D. passwd

  Correct Answer: C

• Question 344:

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

  A. X11 provides graphical display capabilities

  B. X11 provides command line capabilities

  C. X11 provides networking capabilities

  D. X11 provides telephony capabilities.

  Correct Answer: A

  Reference: https://en.wikipedia.org/wiki/X_Window_System

• Question 345:

  A Linux administrator is testing a new web application on a local laptop and consistently shows the following 403 errors in the laptop's logs:

  

  The web server starts properly, but an error is generated in the audit log. Which of the following settings should be enabled to prevent this audit message?

  A. httpd_can_network_connect = 1

  B. httpd_enable_scripting = 1

  C. httpd_enable_homedirs = 1

  D. httpd_enable_cgi = 1

  Correct Answer: A

• Question 346:

  An administrator needs to change the IP address on a server remotely. After updating the configuration files, a network restart is needed. However, the administrator fears that when the network connection drops, the network restart script will be killed before the new IP address has been set.

  Which of the following commands would prevent the script from being killed?

  A. nohup service network restart

  B. service network restart and

  C. echo "service network restart" | at now

  D. bg service network restart

  Correct Answer: A

• Question 347:

  A junior systems administrator is configuring localization option environment variables. The administrator is given a checklist of tasks with the following requirements:

  1.

  View current settings of the LC_ALL environment variable only.

  2.

  Modify the LANG environment variable to US English Unicode.

  Given this scenario, which of the following should be performed to meet these requirements? (Choose two.)

  A. echo $LC_ALL

  B. locale

  C. cat $LC_ALL

  D. export LANG = en_US.UTF-8

  E. export $LANG = en_US.UTF

  F. stty

  Correct Answer: BD

  Reference: https://www.tecmint.com/set-system-locales-in-linux/

• Question 348:

  A Linux administrator needs to switch from text mode to GUI. Which of the following runlevels will start the GUI by default?

  A. Runlevel 3

  B. Runlevel 4

  C. Runlevel 5

  D. Runlevel 6

  Correct Answer: C

  Reference: http://www.linfo.org/runlevel_def.html

• Question 349:

  A networked has been crashing intermittently. A Linux administrator would like to write a shell script that will attempt to ping the server and email an alert if the server fails to respond. The script will later be scheduled via cron job.

  

  Which of the following scripts would BEST accomplish this task?

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: D

• Question 350:

  A Linux administrator is testing connectivity to a remote host on a shared terminal. The administrator wants to allow other users to access the terminal while the command is executing.

  Which of the following commands should the administrator use?

  A. bg ping remotehost

  B. fg ping remotehost

  C. ping remotehost < results

  D. ping remotehost and

  Correct Answer: C