1.09.2Basic
Show journal entries with priority err and the more severe crit, alert, and emerg levels.
Which command is appropriate?
× Incorrect
journalctl -p PRIORITY filters to the selected priority and more severe levels. -p err covers err through emerg.
Detailed explanation
Incorrect
journalctl -t errIncorrect. -t selects an identifier tag.
Correct
journalctl -p errCorrect. -p err selects err and more severe entries.
Incorrect
journalctl -u errIncorrect. -u selects a systemd unit.
Incorrect
journalctl -b errIncorrect. -b selects a boot, not a priority.
Try it yourself
An example you can run in a temporary verification environment.
journalctl --help | grep -E -- '-p|--priority' | head -n 1Expected result
priority filterのhelp行Key points
- -p selects priority
- err is a threshold
- Numeric priorities 0–3 are also usable
Notes
- Environment: systemd journalctl help / journal読取なし
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Syslog facility and priority
Metadata that classifies a message source and its severity.
Journal persistence
Whether systemd journal data survives a reboot and where it is stored.
Log rotation
A process that retains, renames, compresses, or removes log generations.
Question IDKL-102-1095
Environmentsystemd journalctl help / journal読取なし
Last technical review2026-08-13
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