1. What does journalctl -u sshd -f do?
Junior- A.follow live logs for the sshd unit
- B.prune the journal to a maximum size
- C.show logs since the last boot
- D.follow the system log live
Linux · Logging interview questions
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1. What does
Junior2. Which command will follow live logs for the sshd unit?
Junior- A.journalctl -u sshd -f
- B.journalctl --since '1 hour ago'
- C.journalctl -p err
- D.journalctl -b
3. Which statement is correct?
Junior- A.journalctl -u sshd -f — show log entries of priority error and above
- B.journalctl -u sshd -f — write a custom message to the system log
- C.journalctl -u sshd -f — follow live logs for the sshd unit
- D.journalctl -u sshd -f — follow the system log live
4. What does journalctl -b do?
Junior- A.show logs since the last boot
- B.show log entries of priority error and above
- C.print kernel ring-buffer messages
- D.prune the journal to a maximum size
5. Which command will show logs since the last boot?
Junior- A.logger 'test'
- B.dmesg
- C.journalctl -u sshd -f
- D.journalctl -b
6. Which statement is correct?
Junior- A.journalctl -b — print kernel ring-buffer messages
- B.journalctl -b — follow live logs for the sshd unit
- C.journalctl -b — show log entries from the last hour
- D.journalctl -b — show logs since the last boot
7. What does journalctl -p err do?
Mid- A.print kernel ring-buffer messages
- B.follow live logs for the sshd unit
- C.write a custom message to the system log
- D.show log entries of priority error and above
8. Which command will show log entries of priority error and above?
Mid- A.journalctl -b
- B.logger 'test'
- C.journalctl -p err
- D.journalctl --since '1 hour ago'
9. Which statement is correct?
Mid- A.journalctl -p err — show log entries of priority error and above
- B.journalctl -p err — show log entries from the last hour
- C.journalctl -p err — follow live logs for the sshd unit
- D.journalctl -p err — write a custom message to the system log
10. What does dmesg do?
Junior- A.show log entries of priority error and above
- B.prune the journal to a maximum size
- C.write a custom message to the system log
- D.print kernel ring-buffer messages
11. Which command will print kernel ring-buffer messages?
Junior- A.tail -f /var/log/messages
- B.dmesg
- C.journalctl --since '1 hour ago'
- D.journalctl -b
12. Which statement is correct?
Junior- A.dmesg — write a custom message to the system log
- B.dmesg — show log entries from the last hour
- C.dmesg — print kernel ring-buffer messages
- D.dmesg — prune the journal to a maximum size
13. What is logrotate?
Mid- A.a log category like auth, cron, mail or kern
- B.the general system message log (RHEL)
- C.the tool that rotates, compresses and prunes log files
- D.the log file recording authentication and sudo events (RHEL)
14. Which term means: "the tool that rotates, compresses and prunes log files"?
Mid- A./var/log/messages
- B./var/log/secure
- C.logrotate
- D.journald persistent storage
15. Which statement is correct?
Mid- A.logrotate — the tool that rotates, compresses and prunes log files
- B.logrotate — a log category like auth, cron, mail or kern
- C.logrotate — the log file recording authentication and sudo events (RHEL)
- D.logrotate — the general system message log (RHEL)
16. What is /var/log/secure?
Junior- A.the general system message log (RHEL)
- B.keeping logs across reboots by creating /var/log/journal
- C.a log category like auth, cron, mail or kern
- D.the log file recording authentication and sudo events (RHEL)
17. Which term means: "the log file recording authentication and sudo events (RHEL)"?
Junior- A./var/log/messages
- B.rsyslog facility
- C.logrotate
- D./var/log/secure
18. Which statement is correct?
Junior- A./var/log/secure — the log file recording authentication and sudo events (RHEL)
- B./var/log/secure — keeping logs across reboots by creating /var/log/journal
- C./var/log/secure — the general system message log (RHEL)
- D./var/log/secure — the tool that rotates, compresses and prunes log files
19. What does tail -f /var/log/messages do?
Junior- A.show logs since the last boot
- B.write a custom message to the system log
- C.show log entries of priority error and above
- D.follow the system log live
20. Which command will follow the system log live?
Junior- A.tail -f /var/log/messages
- B.journalctl -p err
- C.logger 'test'
- D.journalctl -b
21. Which statement is correct?
Junior- A.tail -f /var/log/messages — follow the system log live
- B.tail -f /var/log/messages — write a custom message to the system log
- C.tail -f /var/log/messages — show log entries of priority error and above
- D.tail -f /var/log/messages — print kernel ring-buffer messages
22. What does logger 'test' do?
Junior- A.print kernel ring-buffer messages
- B.show logs since the last boot
- C.follow the system log live
- D.write a custom message to the system log
23. Which command will write a custom message to the system log?
Junior- A.journalctl --vacuum-size=500M
- B.journalctl --since '1 hour ago'
- C.tail -f /var/log/messages
- D.logger 'test'
24. Which statement is correct?
Junior- A.logger 'test' — write a custom message to the system log
- B.logger 'test' — prune the journal to a maximum size
- C.logger 'test' — follow the system log live
- D.logger 'test' — show logs since the last boot
25. What does journalctl --vacuum-size=500M do?
Mid- A.prune the journal to a maximum size
- B.show log entries from the last hour
- C.show logs since the last boot
- D.show log entries of priority error and above
26. Which command will prune the journal to a maximum size?
Mid- A.journalctl --vacuum-size=500M
- B.tail -f /var/log/messages
- C.logger 'test'
- D.journalctl --since '1 hour ago'
27. Which statement is correct?
Mid- A.journalctl --vacuum-size=500M — print kernel ring-buffer messages
- B.journalctl --vacuum-size=500M — follow the system log live
- C.journalctl --vacuum-size=500M — prune the journal to a maximum size
- D.journalctl --vacuum-size=500M — show log entries from the last hour
28. What does journalctl --since '1 hour ago' do?
Mid- A.prune the journal to a maximum size
- B.write a custom message to the system log
- C.follow live logs for the sshd unit
- D.show log entries from the last hour
29. Which command will show log entries from the last hour?
Mid- A.journalctl --vacuum-size=500M
- B.journalctl --since '1 hour ago'
- C.journalctl -p err
- D.journalctl -b
30. Which statement is correct?
Mid- A.journalctl --since '1 hour ago' — follow the system log live
- B.journalctl --since '1 hour ago' — show log entries from the last hour
- C.journalctl --since '1 hour ago' — follow live logs for the sshd unit
- D.journalctl --since '1 hour ago' — print kernel ring-buffer messages
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