journalctl: how to display colors in its output?
The output of journalctl
really looks messy without colors. Is it possible to add colors to its output? On my system it seems only important lines are highlighted. Even dmesg
can output with color by adding the --color
switch!
Solution 1:
The color support of journalctl
is documented in man journalctl
:
When outputting to a tty, lines are colored according to priority: lines of level ERROR and higher are colored red; lines of level NOTICE and higher are highlighted; other lines are displayed normally.
That's from systemd 229. As seen in the man page, There are no other built-in color controls for journalctl
.
Solution 2:
If the original daemon output is already colorized, but the colors are being lost when using journalctl
, the --output cat
option will restore them. See the manual for more details.
Solution 3:
Install ccze, then use it like this:
journalctl -b -k -f | ccze [-A] [-o nolookups]
explanation:
-A, --raw-ansi
If one wants to enable raw ANSI color sequences instead of using curses, this option does just that.
-o, --options OPTIONS...
However, lookups is an option that might be better to disable. When on, ccze will try to look up usernames, service
names, and lots of other stuff, which will slow down coloring a great deal. If one is piping a long log through ccze,
this option might be turned off [nolookups] to speed up the process.
Solution 4:
I use ccze
for all the logs.
Example for jornalctl with color.
journalctl -b -k -f | ccze
journalctl -b -k -f | ccze -A
Other examples.
tail -f /etc/nginx/logs/access.log | ccze
tail -f /etc/unbound/unbound.log | ccze
Exporting logs
to export the log to HTML and save it to /root/syslog.html:
ccze -h -o nolookups /root/syslog.html
I hope you find it useful.