With the recent update to MariaDB 11, the health check in the sample docker-compose leaves the container showing as unhealthy with an error output:

OCI runtime exec failed: exec failed: unable to start container process: exec: "mysqladmin": executable file not found in $PATH: unknown

Appears this is expected behaviour due to the removal of mysqladmin and suggests an alternative method to track container health using a healthcheck.sh script:

https://mariadb.org/mariadb-server-docker-official-images-healthcheck-without-mysqladmin/