Hello,

not strictly related to Kamailio, but I know a large number of its deployments run with MariaDB.

Be aware of a (pretty high) risk of failure after upgrading MariaDB server to v10.3.31, which comes now on Debian 10 via the usual apt update+upgrade. I was hit on one the servers I upgraded recently, first one worked fine, the 2nd failed to start MariaDB service after upgrade - there is a bug report about it:

* https://www.mail-archive.com/debian-bugs-dist@lists.debian.org/msg1823336.ht...

Downgrading MariaDB seems to be the right solution for now, specially if you didn't do a backup just before upgrade. Don't try other tricks without a fresh backup, data files can be damaged.

If you have a fresh backup, there seems to be a solution by deleting database files to start with a clean set and then restore from backup with sql statements.

FreeBSD has a similar bug report, so doesn't seem to be only Debian, could be other Linux distros as well.

Even with fresh backups, plan for a longer maintenance time frame than usual.

Cheers, Daniel