title: Problem with Starting MySQL Server after upgrade from Ubuntu 18.04 to 20.04
body: <p>I have a problem to start MySQL after an upgrade from Ubuntu 18.04 to 20.04 (MySQL 5.7 to 8). When I tried to start the mysql service kit stops at &quot;Starting MySQL Community Server...&quot;.</p>
  <pre><code>USER@SERVER:~$ systemctl status mysql.service
  ● mysql.service - MySQL Community Server
       Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
       Active: activating (start) since Wed 2020-08-19 11:38:13 CEST; 576ms ago
      Process: 18006 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
     Main PID: 18014 (mysqld)
       Status: &quot;Server startup in progress&quot;
        Tasks: 13 (limit: 1110)
       Memory: 261.6M
       CGroup: /system.slice/mysql.service
               └─18014 /usr/sbin/mysqld
  
  Aug 19 11:38:13 SERVER systemd[1]: Starting MySQL Community Server...
  </code></pre>
  <p>The journal gives me back the following.</p>
  <pre><code>USER@SERVER:~$ journalctl -xe
  
  
  --
  -- The job identifier is 24060.
  Aug 19 11:38:17 boris-dev systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE
  -- Subject: Unit process exited
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- An ExecStart= process belonging to unit mysql.service has exited.
  --
  -- The process' exit code is 'exited' and its exit status is 1.
  Aug 19 11:38:17 boris-dev systemd[1]: mysql.service: Failed with result 'exit-code'.
  -- Subject: Unit failed
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- The unit mysql.service has entered the 'failed' state with result 'exit-code'.
  Aug 19 11:38:17 boris-dev systemd[1]: Failed to start MySQL Community Server.
  -- Subject: A start job for unit mysql.service has failed
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- A start job for unit mysql.service has finished with a failure.
  --
  -- The job identifier is 24060 and the job result is failed.
  Aug 19 11:38:17 boris-dev systemd[1]: mysql.service: Scheduled restart job, restart counter is at 139.
  -- Subject: Automatic restarting of a unit has been scheduled
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- Automatic restarting of the unit mysql.service has been scheduled, as the result for
  -- the configured Restart= setting for the unit.
  Aug 19 11:38:17 boris-dev systemd[1]: Stopped MySQL Community Server.
  -- Subject: A stop job for unit mysql.service has finished
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- A stop job for unit mysql.service has finished.
  --
  -- The job identifier is 24126 and the job result is done.
  Aug 19 11:38:17 boris-dev systemd[1]: Starting MySQL Community Server...
  -- Subject: A start job for unit mysql.service has begun execution
  -- Defined-By: systemd
  -- Support: http://www.ubuntu.com/support
  --
  -- A start job for unit mysql.service has begun execution.
  --
  -- The job identifier is 24126.
  </code></pre>
  <p>There are a few databases and it would be nice to keep them, but not necessary.</p>
  <p>Any idea what's best to do?</p>
  <p>Thanks in advance</p>
  <p>Bo</p>