Hi, thank you taking the time to report this bug and helping to make Ubuntu better.
As explained by Elena Stepanova on https://jira.mariadb.org/browse/MDEV-11170?page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel&focusedCommentId=90592: >There is nothing for Ubuntu to be ashamed of. >It's not a bug that 10.0 cannot start on MySQL 5.7 datadir, it is not expected >to. >Backward compatibility between major versions, in general, might work, but it >has never been guaranteed, neither by MySQL, nor by MariaDB, nor by the >majority of software products. >10.0 was first released years before MySQL 5.7, it couldn't possibly be >designed to be compatible with a version which didn't even exist at the time. Instead of preventing the installation, there is a clear warning that invites you to first export your DB to be able to import them in MariaDB. But the original mysql data dir is not delete during the upgrade process (and will never be). Please find a workaround here to rollback on mysql-5.7 if needed: https://jira.mariadb.org/browse/MDEV-11170?focusedCommentId=106653&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-106653 ** Changed in: mariadb-10.0 (Ubuntu) Status: New => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1656393 Title: MariaDB Fails to Handle MySQL 5.7 Data Changes - Upgrade Results in a Complete Loss of Databases and Data To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mariadb-10.0/+bug/1656393/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
