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Questions[journalctl](server)

Martin Hope
Konstantin
Asked: 2024-04-05 20:15:55 +0800 CST
  • 5

I type a command in CentOS:

sudo journalctl -xe --unit ss

After that, i press Tab and see in the console:

sudo journalctl -xe --unit sshd.service

I type a command in Debian:

sudo journalctl -xe --unit ss

After that, i press Tab and ... and nothing happens:

sudo journalctl -xe --unit ss

Why doesn't work autocomplete journalctl in Debian?

journalctl
Martin Hope
amoe
Asked: 2017-02-16 05:41:18 +0800 CST
  • 8

I have several systemd services defined. They log both to disk and also to the systemd journal, which I can monitor using journalctl -n 0 -fu myservice. However, I notice that the logs that I see from the journalctl tail command are often several minutes behind the disk logs. I've confirmed that this is not related to the actual logging configuration used by the daemon, as when I run the daemon manually and it's outputting its logs to standard output on a console, I see the logs immediately.

How can I see log output from journalctl immediately as the service generates it? Either completely unbuffered, or line buffered would be acceptable.

logging systemd journalctl
Martin Hope
ChromeHearts
Asked: 2016-10-01 18:58:13 +0800 CST
  • 39

I am running user-level services in Ubuntu 16.04 LTS. For example, I have my test.service located at ~/.config/systemd/user/test.service.

I was able to run the service by doing

systemctl --user start test.target

However, when I try to read its log using journalctl, I got this error message:

journalctl --user -u test.service
Hint: You are currently not seeing messages from other users and the system.
  Users in the 'systemd-journal' group can see all messages. Pass -q to
  turn off this notice.
No journal files were opened due to insufficient permissions.

How can I use journalctl for user's specific unit?

permissions systemd systemctl ubuntu-16.04 journalctl
Martin Hope
lyoko the
Asked: 2016-08-30 12:01:43 +0800 CST
  • 7

After deleting my /var/log/journal by accident, I am unable to recover from the consequences. systemd-journald keeps failing over and over again every time I try to start it. when I run:

$ journalctl --verify
PASS: /run/log/journal/system.journal

which doesn't bring me one step closer to solve it because /run/log/journal/system.journal is created when I run /usr/lib/systemd/systemd-journald directly, which on it self outputs 

$ /usr/lib/systemd/systemd-journald
Failed to open runtime journal: Invalid argument

Things I have already tried:

  1. cleaning /var/log/journal and/run/log/journal`.
  2. copying /var/log/journal from another machine to both paths, running journalctl --verify to check them, and once again with --file flag.
  3. changing Storage setting in /etc/systemd/journald.conf to Storage=volatile just to disable /var/log/journald.
  4. Rebooting.
systemd journalctl journald
Martin Hope
Jack O'Connor
Asked: 2016-04-08 12:48:40 +0800 CST
  • 28

I'm particularly interested in this for looking at the output of oneshot services that run on a timer. The --unit flag is close, but it concatenates all the runs of the service together. The most obvious way I can think of would be to filter on PID, but that makes me worry about PID reuse / services that fork, and getting the last PID is pretty inconvenient. Is there some other identifier that corresponds to a single run of a service, that I could use to filter the logs?

EDIT: I would happily accept an authoritative "no" if that's the real answer.

journalctl