Problem: Replication stops due to low disk space

Problem

Your LDAP replication (through listener/ notifier) stops on a server due to running out of disk space.

Environment

To prevent the listener to fill the disk you have already set related ucr variables:

ldap/replication/filesystem/limit: 40187996
This variable configures the lower limit for free space in the directory ‘/var/lib/univention-ldap/’, when replication will be stopped. Default is 10 [MiB].

According to this variable the replication on backups and slave servers will be stopped when below 40TB (!).

listener/freespace: 10
This variable configures the lower limit for free space in the directories ‘/var/lib/univention-ldap/’ and ‘/var/lib/univention-directory-listener/’, when the Listener will be stopped. Default is 10 [MiB].

This variable will cause the listener to stop when the limit is reached.
Note In both cases, replication is stopped but in the second one the listener process will end.

Due to a bug the listener simply stops in the second case and does not notify its watchdog. The later realizes there is no more listener process and restarts it. Causing another process stopping due to disk limitation with the watchdog stepping in and restarting… flooding the logs and causing still less disk space.

Solution

Set the first variable to a higher value than the second. Use i.e. these values:
ucr set ldap/replication/filesystem/limit=40 listener/freespace=10