Just hit this bug when trying to change from mysql to mariadb. Solution: reboot after purging mysql and installing mariadb will load the correct AppArmor profile.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1806263 Title: MariaDB 10.1 server won't start when MySQL 5.7 server has been previously installed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mariadb-10.1/+bug/1806263/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs