Our Mailserver is unable to receive emails from other mailservers or forward emails submitted from users.
We are investigating the situation.
The current assumption is that the database behind the mailserver might be broken or unreachable.
Update 16:39
We have successfully tested other components which are using the database cluster in question.
It is unlikely that the database is the source of the problems.
Update 18:00
We have identified a misconfiguration in the mailserver system.
The mailing list software tried to connect to the database using a target IP address,
which was not the high-availability IP.
Thus, during maintenance on the database cluster, the mailing list software was now unable to connect to the database when that one node with the right IP address went offline.
Resolution
The mailserver config has been adjusted so that the highly available IP address will be used in the future.
This should prevent an outage like this in the future.
