“Bad boys, whatcha want. Watcha want, whatcha gonna do when the root is full?”

Actually, what are you gonna do when the journald taking up lots of space? For example, during the operating system upgrade on my desktop, the free space on / is not sufficient.

Error Summary
-------------
Disk Requirements:
   At least 5643MB more space needed on the / filesystem.

So, I check how much space the systemd-journald log was consuming:

[root@watamem log]# journalctl --disk-usage
Archived and active journals take up 3.9G in the file system.

I’d like to decrease the log size to just 10MB. This process is called vacuuming by using --vaccum-size option with journalctl command.

[root@watamem log]# journalctl --vacuum-size=10
...omitted...
Deleted archived journal /var/log/journal/8d0434dbcc454db49d61aa54595268aa/system@4f5d349882204f4d8db4d40456195459-00000000023938a3-0005b13937ae08fe.journal (8.0M).
Vacuuming done, freed 3.8G of archived journals from /var/log/journal/8d0434dbcc454db49d61aa54595268aa.
Vacuuming done, freed 0B of archived journals from /var/log/journal.

That’s all, folks.

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