=== [1] mariadb_upgrade_info — the datadir's OWN record of which version converted it
12.3.3-MariaDB

=== [2] THE ENGINE'S OWN CHECK, authenticated (R-464: never the log line)
This installation of MariaDB is already upgraded to 12.3.3-MariaDB.
There is no need to run mariadb-upgrade again.
exit=1
=== [3] the entrypoint's own lines about the upgrade
2026-09-21 21:40:23+02:00 [Note] [Entrypoint]: Starting mariadb-upgrade
The --upgrade-system-tables option was used, user tables won't be touched.
Major version upgrade detected from 11.6.2-MariaDB to 12.3.3-MariaDB. Check required!
Phase 2/8: Installing used storage engines... Skipped
Phase 4/8: Fixing views... Skipped
Phase 5/8: Fixing table and database names ... Skipped
Phase 6/8: Checking and upgrading tables... Skipped
2026-09-21 21:40:29+02:00 [Note] [Entrypoint]: Finished mariadb-upgrade
=== [4] the engine's OWN pre-upgrade backup file
-rw-r--r-- 1 mysql mysql 631905 Sep 21 21:40 /var/lib/mysql/system_mysql_backup_11.6.2-MariaDB.sql.zst
(no pre-upgrade backup file present)
=== [5] the version actually running
mariadbd  Ver 12.3.3-MariaDB-ubu2404 for debian-linux-gnu on x86_64 (mariadb.org binary distribution)
=== [6] container state
image=mariadb:12.3 running=true restarts=0