On a systemd system, type the journalctl command that restricts the output to kernel messages from the current boot.
LPIC-1 Exam 101-500, objective 101. System architecture medium
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Answer
Type the answer.
Accepted answers
journalctl -kjournalctl --dmesgjournalctl -k -bjournalctl -b -k
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
journalctl -k (long form --dmesg) restricts output to kernel messages and implies -b, so it already limits the output to the current boot. It is the journal's answer to dmesg, with the advantage that it can be combined with a boot offset: journalctl -k -b -1 shows the kernel messages from the previous boot, which the in-memory ring buffer behind dmesg cannot do.
Where this comes from
- Cited
- manual page journalctl(1)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 101 and space the ones you get wrong.
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