0) We have a very similar problem to this bug. Basically we are trying to install mysql-server-5.7 5.7.12-0ubuntu1 package in Ubuntu 16.04 and while installing it we get, among other messages: Job for mysql.service failed because the control process exited with error code. See "systemctl status mysql.service" and "journalctl -xe" for details. 1) In order to get debug information we run: sudo /usr/sbin/mysqld --log-error=/tmp/error.log --log-error-verbosity=2 and the /tmp/error.log contents are: 2016-06-09T11:12:04.525246Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). mysqld: Table 'mysql.plugin' doesn't exist 2016-06-09T11:12:04.635835Z 0 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 2016-06-09T11:12:04.636223Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened. 2016-06-09T11:12:04.636276Z 0 [Warning] Failed to set up SSL because of the following SSL library error: SSL context is not usable without certificate and private key 2016-06-09T11:12:04.636338Z 0 [ERROR] Could not create unix socket lock file /var/run/mysqld/mysqld.sock.lock. 2016-06-09T11:12:04.636344Z 0 [ERROR] Unable to setup unix socket lock file. 2016-06-09T11:12:04.636349Z 0 [ERROR] Aborting 2) If you try to get rid of mysql (BEWARE this would probably delete all your databases) and try to install it again: sudo apt-get remove --purge mysql\* sudo apt-get install mysql-server You get the same problems once again. 3) What causes the problem? Having a partition mounted on /var/lib/mysql directory. 4) How to solve it (workaround) ? BEWARE! DO NOT USE THESE COMMANDS UNLESS IT'S A NEW INSTALLATION WHERE YOU DON'T MIND LOOSING DATA. TL;DR : Install mysql-server without a dedicated mounted partition on /var/lib/mysql. After the installation move the data to the dedicated mounted partition and mount it in /var/lib/mysql. Remove and purge mysql-server package. Remove any file inside /var/lib/mysql directory if it has not been removed. Umount /var/lib/mysql Install mysql-server package (Now it should work flawlessly.) service mysql stop (Make sure service mysql is stopped) Mount your mysql dedicated partition into a temporary directory. E.g. /mnt/newmysql . Use cp -a for copying data from /var/lib/mysql to: /mnt/newmysql Rename or delete /var/lib/msyql Recreate an empty /var/lib/mysql with same permissions, user owner and group owner than the original one. Umount /mnt/newmysql Run 'mount -a' so that your dedicated partition for mysql is mounted on: /var/lib/mysql service mysql start Mysql works ok till, probably, the next update if Ubuntu has not fixed this bug on their side. 5) How to solve it (Correct fix) ? Somewhere in the package post-installation or configuration scripts or even mysql upstream scripts is different between latest version (php 5.5) and current one (php 5.7). This difference implies handling having a separated partition for /var/lib/mysql . I suspect that somewhere in the installation it tries to remove /var/lib/mysql directory (e.g. expects to be able to remove completely that directory) and, because of that folder having a partition mounted on it, it cannot be removed. Please package maintainer try to simulate this problem in a VM and fix the package for this not to happen. 6) Feedback. In order to know if what I am describing is another bug or this same bug we need feedback from the other people who have reported this bug. So... the question is: * Did you also have a dedicated partition mounted on /var/lib/msyql ? * Or did you have any other dedicated partition elsewhere related to mysql? If you don't have any of these dedicated partition I guess that running: sudo /usr/sbin/mysqld --log-error=/tmp/mysql-1562362-error.log --log-error-verbosity=3 and attaching / copying here the /tmp/mysql-1562362-error.log contents will help the package maintainer on classifying your bug.