I´ve searched a little bit at the community and it seems that there were similar problems, but I couldn´t solve it by the advices given so far. I can´t start IcingaDB anymore at my ubuntu vm. Error: unexpected database schema version: v3 (expected v4), please make sure you have applied all database migrations after upgrading Icinga DB
I´ve checked if there are open migration at icinga director and with
icingacli director migration pending --verbose
Also I tried:
icinga-redis-cli flushall
But nothing helped so far: I haven´t found any upgrade schema at /usr/share/doc/icingadb/ or /usr/share/icingadb/schema/mysql/upgrades/ which could be related to the problem. The most recent upgrade version is 1.1.1.sql. Has anyone a hint, how I could solve / debug this further?
There is no auto-updating mechanism in Icinga. Updates are only triggered by your package manager.
If you are manually performing upgrades, you can hold packages as @moreamazingnick suggested. If you are using unattended upgrades, you can exclude packages (Unattended-Upgrade::Package-Blacklist for Debian/Ubuntu).
In general, it is advisable to not auto-upgrade Icinga packages since there are certain version upgrades requiring manual intervention. Personally, I have excluded all icinga packages from unattended upgrades and monitor required upgrades to not miss any.