Logs flooded with systemd messages: Created slice & Starting Session

By Vinny Wang 2018-03-29

https://access.redhat.com/solutions/1564823

Environment

Red Hat Enterprise Linux 7

Issue

On my RHEL7 newely installed system I am seeing the following in /var/log/messages all the time

Jul 24 08:50:01 example.com systemd: Created slice user-0.slice.
Jul 24 08:50:01 example.com systemd: Starting Session 150 of user root.
Jul 24 08:50:01 example.com systemd: Started Session 150 of user root.
Jul 24 09:00:01 example.com systemd: Created slice user-0.slice.
Jul 24 09:00:02 example.com systemd: Starting Session 151 of user root.
Jul 24 09:00:02 example.com systemd: Started Session 151 of user root.

Resolution

These messages are normal and expected — they will be seen any time a user logs in

To suppress these log entries in /var/log/messages, create a discard filter with rsyslog, e.g., run the following command:

echo 'if $programname == "systemd" and ($msg contains "Starting Session" or $msg contains "Started Session" or $msg contains "Created slice" or $msg contains "Starting user-" or $msg contains "Starting User Slice of" or $msg contains "Removed session" or $msg contains "Removed slice User Slice of" or $msg contains "Stopping User Slice of") then stop' >/etc/rsyslog.d/ignore-systemd-session-slice.conf

Then restart the rsyslog service

systemctl restart rsyslog

Note In case above rule only works for local syslog logging(/var/log/messages) but doesn’t work for remote syslog server then we can understand this rule is read after syslog events are sent to syslog server. So in order to avoid this add the rule directly in rsyslog.conf above the line of remote syslog sending configuration. (. @@sys-log server)