LCA Cheat Sheet 2026

The 30 highest-yield LCA facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. In the context of LCA certification, what is the most important consideration when implementing backup & disaster recovery? → Ensuring alignment with established standards, stakeholder needs, and best practices
2. Which command checks and repairs a Linux file system? → fsck
3. What does the Linux command 'iptables' manage? → Network traffic filtering
4. Which bootloader is most commonly installed with Linux systems? → GRUB
5. In the context of LCA certification, what is the most important consideration when implementing web server & database administration? → Ensuring alignment with established standards, stakeholder needs, and best practices
6. What port number does SSH use by default? → 22
7. What happens when you append an ampersand (&) to a shell command such as 'long-script.sh &'? → The command runs in the background, freeing the terminal for other commands
8. Which journalctl command filters log output to show only entries from the systemd unit named 'nginx'? → journalctl -u nginx
9. What is the primary purpose of the /proc virtual filesystem in Linux? → To provide a kernel interface exposing process and system information
10. Which of the following best describes a key competency required for network configuration & troubleshooting in LCA practice? → Strong analytical skills combined with effective communication and ethical judgment
11. In the context of LCA certification, what is the most important consideration when implementing network configuration & troubleshooting? → Ensuring alignment with established standards, stakeholder needs, and best practices
12. Which of the following ports should be closed to reduce attack surface on a server? → Unused services ports
13. Which systemctl command enables a service to start automatically at system boot? → systemctl enable
14. During installation, what does setting the root password accomplish? → It secures the admin account
15. What command runs a shell script named 'myscript.sh'? → sh myscript.sh
16. Which loop is used to iterate over a list of items in shell scripting? → for
17. Which signal cannot be caught, blocked, or ignored by any process, including processes running as root? → SIGKILL (9)
18. In the context of LCA certification, what is the most important consideration when implementing package management & software installation? → Ensuring alignment with established standards, stakeholder needs, and best practices
19. How do you execute a command stored in a variable? → eval $VAR
20. Which of the following best describes a key competency required for cloud integration & deployment in LCA practice? → Strong analytical skills combined with effective communication and ethical judgment
21. Which symbol is used to start a comment line in a shell script? → #
22. In the context of LCA certification, what is the most important consideration when implementing user & permission management? → Ensuring alignment with established standards, stakeholder needs, and best practices
23. What happens when a process receives SIGTERM (signal 15)? → It receives a graceful termination request and can perform cleanup before exiting
24. Which file contains the persistent mount information in Linux? → /etc/fstab
25. What is the role of the /etc/fstab file in Linux? → It defines disk partitions and mount points
26. Which command provides a dynamic, real-time, auto-refreshing view of system processes sorted by resource usage? → top
27. What is the primary purpose of the 'at' command in Linux? → To schedule a one-time command to execute at a specified future time
28. Which of the following best describes a key competency required for web server & database administration in LCA practice? → Strong analytical skills combined with effective communication and ethical judgment
29. What command reloads firewall rules in firewalld? → firewall-cmd --reload
30. Which of the following best describes a key competency required for package management & software installation in LCA practice? → Strong analytical skills combined with effective communication and ethical judgment