That is the default traditional format.
To output log levels in messages (technically known as priorities), you should change the default template used by rsyslog
:
open with admin privileges the file /etc/rsyslog.conf
and add the following lines
$template precise,"%syslogpriority%,%syslogfacility%,%timegenerated%,%HOSTNAME%,%syslogtag%,%msg%\n"
$ActionFileDefaultTemplate precise
after the line
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat
restart the daemon, with the command:
sudo service rsyslog restart
Now you should see lines like the following:
6,5,Nov 18 10:17:02,acer,rsyslogd:, [origin software="rsyslogd" swVersion="5.8.1" x-pid="7064" x-info="http://www.rsyslog.com"] exiting on signal 15.
where the first two numbers (6 and 5) represent respectively the priority and the facility, where the priority is given by
7 - debug
6 - info
5 - notice
4 - warning, warn
3 - err, error
2 - crit,
1 - alert,
0 - emerg, panic
and the facilities can be seen in the syslog(3)
man page.