830

I check service status with systemctl status service-name.

By default, I see few rows only, so I add -n50 to see more.

Sometimes, I want to see full log, from start. It could have 1000s of rows.
Now, I check it with -n10000 but that doesn't look like neat solution.

Is there an option to check full systemd service log similar to less command?

Gilles 'SO- stop being evil'
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10robinho
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    While the accepted answer wasn't useful for me, I was not aware of the `-n` flag. Adding `-n99999` seems to be an acceptable workaround for me. Thanks for pointing me in the right direction :-) – tobixen Jun 26 '19 at 05:00
  • The fags can be found [here](https://serverfault.com/questions/978428/systemctl-status-log-output). `systemctl -l --no-pager status ` – Richard Tyler Miles Sep 15 '22 at 15:12

6 Answers6

1185

Just use the journalctl command, as in:

journalctl -u service-name.service

Or, to see only log messages for the current boot:

journalctl -u service-name.service -b

For things named <something>.service, you can actually just use <something>, as in:

journalctl -u service-name

But for other sorts of units (sockets, targets, timers, etc), you need to be explicit.

In the above commands, the -u flag is short for --unit, and specifies the name of the unit in which you're interested. -b is short for --boot, and restricts the output to only the current boot so that you don't see lots of older messages. See the journalctl man page for more information.

larsks
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    appending `--no-pager` will print full log, so you wont have to scroll – Dushyant Bangal May 29 '17 at 11:41
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    appending `-e` will start the log at the end removing the need to scroll, but without printing the entire log beforehand. – timlyo Jul 28 '17 at 14:45
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    appending `-f` will follow (print) updates to the log – Joe J Sep 06 '17 at 17:10
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    appending `--help` will let you see all available options – Tzafrir Mar 26 '18 at 20:14
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    are these logs being stored somewhere on the disk? – viveksinghggits Apr 11 '19 at 10:09
  • @viveksinghggits generally, although it depends on your configuration, but you still need to use `journalctl` to access them. – larsks Apr 11 '19 at 11:43
  • got it @larsks. `https://www.freedesktop.org/software/systemd/man/systemd-journald.service.html` – viveksinghggits Apr 11 '19 at 11:58
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    Actually, this was not helpful for me - I want only the output since the unit was (re)started. `sudo systemctl -n 99999 status` gives me that, but apparently journalctl can only filter "from boot", not "from service start". – tobixen Jun 26 '19 at 04:57
  • I assume `--no-pager` will allow it to be piped? (say, to `grep`?) – DarthCadeus Nov 07 '19 at 14:10
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    `--no-pager` is not necessary when piping the output. It's only useful to disable the pager when output is to an interactive terminal. `journalctl` does not use a pager when you're piping the output to something else. – larsks Nov 07 '19 at 14:12
  • You can combine/append multiple units (`-u`) and thus combine the log of multiple services. – rugk Jul 28 '20 at 12:32
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    You can use `shift-g` to jump to the end of file in `less` or similar pagers. – Matthias Sep 03 '20 at 22:14
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    Appending `-o cat` will remove systemd log text processing so you can see the output as the process produced it. – fuzzyTew Jun 30 '21 at 10:11
  • NB: do NOT use `journalctl UNIT=foobar.service` thinking like me that it's the same as `journalctl -u foobar.service`, because it's not! With `UNIT=` sudo commands coming from a custom script are not listed; they are displayed with `-u`. – 4wk_ Jan 19 '22 at 16:28
  • whatever options I choose, I get `-- No entries --` – Alecz Sep 14 '22 at 17:18
61

systemctl can include the complete output of its status listing, without truncation., by adding the -l flag:

systemctl -l status service-name

-l: don't truncate entries with ellipses (...)

--no-pager can be added to avoid invoking a pager when the output is an interactive terminal.

erik258
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Julien
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    Could you explicit your answer somehow? Adding some explanation about the options, and don't hesitate to [format](https://stackoverflow.com/editing-help) your answer! – joH1 Jan 24 '18 at 10:20
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    This answer is wrong. The output stays truncated. – phil294 Oct 30 '18 at 14:21
  • might not be best for current one, but gods... it will make my life easier going forward :D – Tom St Aug 14 '21 at 14:51
  • Since this no longer works on my system, I've posted [another answer](https://unix.stackexchange.com/a/673548/353063) that makes it posible to get the full logs via `systemctl` (with full support to journalctl's options to boot). It's a hack but it's been working great for me so far. – Tenders McChiken Oct 17 '21 at 08:22
33

Use journalctl to View Your System's Logs

View journalctl without PagingPermalink To send your logs to standard output and avoid paging them, use the --no-pager option:

journalctl --no-pager

It’s not recommended that you do this without first filtering down the number of logs shown.

journalctl -u service-name.service

Show Logs within a Time RangePermalink Use the --since option to show logs after a specified date and time:

journalctl --since "2018-08-30 14:10:10"

Use the --until option to show logs up to a specified date and time:

journalctl --until "2018-09-02 12:05:50"

Combine these to show logs between the two times:

journalctl --since "2018-08-30 14:10:10" --until "2018-09-02 12:05:50"

More info

champion-runner
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25

Most of the time, it is convenient and easy to use the following bash command:

journalctl -xefu service-name.service

or

journalctl -xefu service-name

It works as if the process is executed via shell and the output is changing dynamically (similar to tail -f).

AdminBee
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Berk Sudan
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    This is the only answer that shows if a unit has been started or stopped (or likewise restart). – Dave Mar 11 '22 at 14:19
17

using journalctl

write logs to a text file

and read it bottom up

journalctl -u service-name.service > file_name.txt

tail file_name.txt
J11
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2

Since @Julien's answer no longer appears to work on my system (Debian 11), I've finally given in and hijacked systemctl on my system:

systemctl() { 
    if [[ "${1-}" == "log" ]]; then  
        /usr/bin/journalctl -u "${@:2}"; 
    else /usr/bin/systemctl "$@";
    fi 
}

Add this oneliner to your .bashrc and your systemctl will gain a new log "verb" that provides the missing functionality. No more wasting time retyping tedious commands.

As an added bonus, this method will also give you access to all the options of journalctl (provided that they're specified after the unit name):

systemctl log named.service --since=today
Tenders McChiken
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