Hello Simon and thanks for your bug report and for the detailed steps to reproduce it. The command causing the error is mysql_upgrade, which can also be run manually, without triggering the execution of the postinst.
The command has been dropped in mysql-8, as the upgrade is now done automatically by the mysql daemon on startup. What you are hitting seems to be a limitation of mysql/mysql_upgrade. We could avoid running mysql_upgrade if mysql is configured in (super -)read-only mode, but we'd need a reliable way to check if that's the case even if the daemon is not running, and still I'd not be really aware of the implications of skipping the mysql_upgrade runs. While I acknowledge the situation is not ideal, I'm not sure on how we can safely improve on your setup. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1889472 Title: mysql-server-5.7 postinst fails when in read-only mode To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mysql-5.7/+bug/1889472/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
