practice task
List Failed systemd Units
After a reboot, a host is reachable but something feels broken. You need a quick inventory of failed units before digging into individual logs.
Independent study support only. No affiliation, endorsement, exam dumps, or guaranteed exam results.
Try first
systemctl --failed --no-pagerGoal
Find failed units and choose one unit to inspect with status and journal output.
Expected output
A list of failed loaded units, usually with UNIT, LOAD, ACTIVE, SUB, and DESCRIPTION columns. No failed units means the list should be empty.
Teaches
Use systemd's own failed-unit state as the first triage list after boot or deploy.
Common mistake
Restarting services one by one without first seeing which units systemd already marked as failed.
command set
Commands to know
systemctl --failedsystemctl status UNIT --no-pagerjournalctl -u UNIT -b --no-pager
Related lessons
Watch this command run
Example output from a temporary Linux lab
List Failed systemd Units
Review the related command card and compare your expected output with the command replay.
Watch command runRead One Unit's Logs Since Boot
Review the related command card and compare your expected output with the command replay.
Watch command runnext practice
Check Pending Package Updates
A Debian or Ubuntu server may be missing important updates. You need to list pending upgrades without installing anything.