How to see full log from systemctl status service?

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?

Answers:

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Method 1

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.

Method 2

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.

Method 3

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

Method 4

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).

Method 5

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

Method 6

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 "[email protected]";
    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

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0