Question
Which cronjobs run on UCS by default?
Answer
UCS uses cron and cronjobs out-of-the-box mainly for housekeeping. If you want to add your own cronjobs, have a look at Univention Corporate Server
The following lists cover the default cronjobs of UCS 4.4 with UCS@school and Self-Service installed. Please note that additional components, Apps or third-party software might add their own cronjobs.
Monthly, Weekly, Daily, Hourly
Some cronjobs are executed “once per day” or “once per week”. If you want to know when exactly these cronjobs are executed, have a look at /etc/crontab. The defaults are:
| Interval | Time |
|---|---|
| Monthly | every first day of the month at 06:52 |
| Weekly | every sunday at 06:47 |
| Daily | every day at 06:25 |
| Hourly | every hour at minute 17, or “seventeen minutes past a full hour” |
| Cronjob | Description | Execution | Comment |
|---|---|---|---|
/etc/cron.weekly/man-db |
update the manual page index caches | weekly | housekeeping |
/etc/cron.daily/apache2 |
run htcacheclean
|
daily | inactive by default |
/etc/cron.daily/apt-compat |
fallback for apt.systemd.daily
|
daily | inactive by default, runs as systemd timer instead |
/etc/cron.daily/bsdmainutils |
calendar daily maintenance script | daily | inactive by default |
/etc/cron.daily/cracklib-runtime |
update password check dictionary | daily | housekeeping |
/etc/cron.daily/dpkg |
backup the dpkg databases |
daily | housekeeping |
/etc/cron.daily/locate |
update the locatedb database |
daily | housekeeping |
/etc/cron.daily/logrotate |
rotate logfiles according to logrotate.conf
|
daily | housekeeping |
/etc/cron.daily/man-db |
update the manual page index caches, remove old cache | daily | housekeeping |
/etc/cron.daily/ntp |
compress old and delete even older ntpstats
|
daily | housekeeping |
/etc/cron.daily/passwd |
copy shadow, passwd files to /var/backups/
|
daily | housekeeping |
/etc/cron.daily/quota |
run warnquota to inform users of their quota |
daily | inactive by default |
/etc/cron.daily/sysstat |
get a summary of process accounting | daily | inactive by default |
/etc/cron.daily/univention-ssl |
checks validity of root and host certificate and updates the CRL validity | daily | housekeeping |
Please note: “inactive by default” means, that cron does run the cronjob, but the cronjob itself checks for certain conditions. Those conditions are not met by default. For example the quota cronjob checks if run_warnquota is set to true in /etc/default/quota (which is empty/false by default).
Fixed time
| Cronjob | Description | Execution | Comment |
|---|---|---|---|
/etc/cron.d/mrtg |
create mrtg stats and graphics (CPU, RAM, SWAP) | every 5 minutes | housekeeping |
/etc/cron.d/php |
remove old session files | 09 and 39 minutes past full hour | inactive by default, runs as systemd timer instead |
/etc/cron.d/postgresql |
database maintenance (vacuum) | 2 minutes past every 5 hours, full vacuum on sundays at 03:10 | housekeeping |
/etc/cron.d/sysstat |
get a summary of process accounting | every 10 minutes | inactive by default |
/etc/cron.d/sysvol-cleanup |
run sysvol-cleanup.py
|
every day at 04:04 | only relevant if UCS provides AD DS |
/etc/cron.d/sysvol-sync |
run sysvol-sync.sh
|
every 5 minutes | only relevant if UCS provides AD DS |
/etc/cron.d/ucs-school-import |
purge expired users (ucsschoolPurgeTimestamp) |
every day at 04:50 | UCS@school user maintenance |
/etc/cron.d/ucs-school-umc-exam-master |
cleanup UCS@school exam mode | every day at 03:30 | inactive by default |
/etc/cron.d/univention-config-registry-backup |
create backup of local UCR file backend | every day at 03:30 | housekeeping |
/etc/cron.d/univention-directory-policy |
read and apply current policies from LDAP | 5 minutes past every hour | housekeeping |
/etc/cron.d/univention-directory-reports-cleanup |
cleanup old Univention directory report files | every day at 00:00 | housekeeping |
/etc/cron.d/univention-home-mounter |
unmount unused auto-mounts of homedir | every 10 minutes | housekeeping |
/etc/cron.d/univention-ldap |
create new Diffie-Hellman-Parameter for TLS key exchange | every day at 04:30 | housekeeping |
/etc/cron.d/univention-ldap-server |
create and compress an OpenLDAP dump as backup | every day at 00:00 | housekeeping |
/etc/cron.d/univention-mail-postfix |
recreate dh parameter files for forward secrecy | no default, needs configuration | inactive by default |
/etc/cron.d/univention-maintenance |
run unattended UCS updates | no default, needs configuration | inactive by default |
/etc/cron.d/univention-mrtg |
create mrtg stats and graphics (CPU, RAM, SWAP) for UMC module | every 15 minutes | housekeeping |
/etc/cron.d/univention-nagios |
reads RAID status for optional Nagios check | every minute | inactive by default |
/etc/cron.d/univention-pam |
run ldap-group-to-file.py for local group cache |
every 15 minutes | housekeeping |
/etc/cron.d/univention-server-{master,backup,slave,member} |
execute server password change (if due) | every day at 01:00 | housekeeping |
/etc/cron.d/univention-ssl |
copy all host certificates from master | every 20 minutes | only if server role is “domaincontroller_backup” |
/etc/cron.d/univention-system-stats |
run univention-system-stats
|
every 30 minutes | housekeeping |
/etc/cron.d/univention-ucr-cronjobs |
run cronjobs defined manually via UCR (see manual) | ||
/etc/cron.d/univention-updater |
run updater statistics | daily and at reboot | housekeeping |
/etc/cron.d/univention-updater-check |
check for available updates | 5 minutes past full hour and at reboot | housekeeping |
systemd timer
Systemd offers an alternative to cron with its timer units. Systemd timers can be run at calendar based time events or on monotonic based time events. By default, the following systemd timers exist on UCS (systemctl status *timer):
-
apt-daily.timer- Daily apt download activities -
apt-daily-upgrade.timer- Daily apt upgrade and clean activities -
phpsessionclean.timer- Clean PHP session files every 30 mins -
systemd-tmpfiles-clean.timer- Daily Cleanup of Temporary Directories