将系统从 14.04 升级到 16.04 后，我无法安装 MySQL

将系统从 14.04 升级到 16.04 后，我无法安装 MySQL

我试图让 MySQL 工作的所有内容都会产生类似的错误，如下所示：

   root@alm:~# sudo dpkg --configure -a
   Setting up mysql-server-5.7 (5.7.29-0ubuntu0.16.04.1) ...
   Renaming removed key_buffer and myisam-recover options (if present)
   Job for mysql.service failed because the control process exited with error code. See "systemctl      status mysql.service" and "journalctl -xe" for details.
invoke-rc.d: initscript mysql, action "start" failed.
     mysql.service - MySQL Community Server
     Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
     Active: activating (auto-restart) (Result: exit-code) since Tue 2020-04-14 11:41:44 EEST; 7ms ago
    Process: 1711 ExecStartPost=/usr/share/mysql/mysql-systemd-start post (code=exited, status=0/SUCCESS)

   Process: 1710 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
   Process: 1700 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited,   status=0/SUCCESS)
   Main PID: 1710 (code=exited, status=1/FAILURE)

   Apr 14 11:41:44 alm.i4ware.fi systemd[1]: Failed to start MySQL Community Se....
   Apr 14 11:41:44 alm.i4ware.fi systemd[1]: mysql.service: Unit entered failed....
   Apr 14 11:41:44 alm.i4ware.fi systemd[1]: mysql.service: Failed with result ....
   Hint: Some lines were ellipsized, use -l to show in full.
   dpkg: error processing package mysql-server-5.7 (--configure):
   subprocess installed post-installation script returned error exit status 1
   dpkg: dependency problems prevent configuration of mysql-server:
   mysql-server depends on mysql-server-5.7; however:
   Package mysql-server-5.7 is not configured yet.

   dpkg: error processing package mysql-server (--configure):
   dependency problems - leaving unconfigured
   Errors were encountered while processing:
   mysql-server-5.7
   mysql-server

systemctl status mysql.service说：

mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: en
   Active: activating (start-post) (Result: exit-code) since Tue 2020-04-14 12:2
  Process: 15717 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
  Process: 15709 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exi
 Main PID: 15717 (code=exited, status=1/FAILURE);         : 15718 (mysql-systemd
   CGroup: /system.slice/mysql.service
           └─control
             ├─15718 /bin/bash /usr/share/mysql/mysql-systemd-start post
             └─15750 sleep 1

Apr 14 12:26:22 alm.i4ware.fi systemd[1]: mysql.service: Service hold-off time o
Apr 14 12:26:22 alm.i4ware.fi systemd[1]: Stopped MySQL Community Server.
Apr 14 12:26:22 alm.i4ware.fi systemd[1]: Starting MySQL Community Server...
Apr 14 12:26:24 alm.i4ware.fi systemd[1]: mysql.service: Main process exited, co
...skipping...
● mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: en
   Active: activating (start-post) (Result: exit-code) since Tue 2020-04-14 12:2
  Process: 15717 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
  Process: 15709 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exi
 Main PID: 15717 (code=exited, status=1/FAILURE);         : 15718 (mysql-systemd
   CGroup: /system.slice/mysql.service
           └─control
             ├─15718 /bin/bash /usr/share/mysql/mysql-systemd-start post
             └─15750 sleep 1

Apr 14 12:26:22 alm.i4ware.fi systemd[1]: mysql.service: Service hold-off time o
Apr 14 12:26:22 alm.i4ware.fi systemd[1]: Stopped MySQL Community Server.
Apr 14 12:26:22 alm.i4ware.fi systemd[1]: Starting MySQL Community Server...
Apr 14 12:26:24 alm.i4ware.fi systemd[1]: mysql.service: Main process exited, co

该怎么办？