Show kernel and service warnings from the current boot
Build a paste-ready command, then review its compatibility and effects before running it.
journalctl -b -p warning..alert --no-pager -o short-isoread-onlyno known side effects Compatibility
LinuxVerified for Linux using bash, zsh syntax.
Operational knowledgereview due 2027-01-19
Requirementsjournalctljournalctl must be installed and available on PATH.
Version supportjournalctl Current supported releasesVerified for linux using bash, zsh syntax; consult compatibility notes for platform-specific differences.
Expected signals2026-07-23T08:12:01+0200 web-01 kernel: nvme nvme0: I/O 42 QID 0 timeoutRepresentative successful output; values vary with the selected target and system state.
Known errorsjournalctl: command not foundjournalctl is missing or is not available on PATH.
Verifyjournalctl -b -p warning..alert --no-pager -o short-isoThe output matches the expected target and exits without an error.Rollback noteNot required: this command is read-only and does not change system state.
Command breakdown
01journalctlCommandRuns the journalctl stage of this one-liner.
02-bOptionConfigures journalctl with the -b option.
03-pOptionSelects the command-specific port, process, or print mode.
04warning..alertArgumentPasses warning..alert to journalctl.
05--no-pagerOptionPrints directly instead of opening an interactive pager.
06-oOptionSelects an output file or output format for this command.
07short-isoArgumentPasses short-iso to journalctl.
This advanced community-curated one-liner combines several stages. Review every option and placeholder before running it.
Example input
journalctl -b -p warning..alert --no-pager -o short-iso
Example output
2026-07-23T08:12:01+0200 web-01 kernel: nvme nvme0: I/O 42 QID 0 timeout
2026-07-23T08:12:09+0200 web-01 systemd[1]: backup.mount: Mount process exited, code=exited, status=32
Illustrative output — exact values vary by system and data.
Official sources