我刚刚在我的 ubuntu 20 服务器上执行了“apt dist-upgrade”，它将 mysql 从 5.7 升级到 8.0，但现在不再起作用了！
Setting up mysql-server-8.0 (8.0.22-0ubuntu0.20.04.2) ...
mysqld will log errors to /var/log/mysql/error.log
2020-11-03T17:13:36.704630Z 0 [ERROR] [MY-010946] [Server] Failed to start mysqld daemon. Check mysqld error log.
Warning: Unable to start the server.
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)
Drop-In: /etc/systemd/system/mysql.service.d
└─override.conf
Active: activating (auto-restart) (Result: exit-code) since Tue 2020-11-03 18:13:53 CET; 20ms ago
Process: 1419 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
Main PID: 1419 (code=exited, status=1/FAILURE)
Status: "Server upgrade complete"
Error: 2 (No such file or directory)
Nov 03 18:13:53 Socrates systemd[1]: Failed to start MySQL Community Server.
dpkg: error processing package mysql-server-8.0 (--configure):
installed mysql-server-8.0 package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
mysql-server-8.0
E: Sub-process /usr/bin/dpkg returned an error code (1)
这些是当前安装的软件包：
ii dbconfig-mysql 2.0.13 all dbconfig-common MySQL/MariaDB support
ii libmysqlclient21:amd64 8.0.22-0ubuntu0.20.04.2 amd64 MySQL database client library
ii mysql-client-8.0 8.0.22-0ubuntu0.20.04.2 amd64 MySQL database client binaries
ii mysql-client-core-8.0 8.0.22-0ubuntu0.20.04.2 amd64 MySQL database core client binaries
ii mysql-common 5.8+1.0.5ubuntu2 all MySQL database common files, e.g. /etc/mysql/my.cnf
ic mysql-server-5.7 5.7.31-0ubuntu0.18.04.1 amd64 MySQL database server binaries and system database setup
iF mysql-server-8.0 8.0.22-0ubuntu0.20.04.2 amd64 MySQL database server binaries and system database setup
ii mysql-server-core-8.0 8.0.22-0ubuntu0.20.04.2 amd64 MySQL database server binaries
这是服务状态：
service mysql status
● mysql.service - MySQL Community Server
Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
Drop-In: /etc/systemd/system/mysql.service.d
└─override.conf
Active: activating (start) since Tue 2020-11-03 18:28:24 CET; 13s ago
Main PID: 4083 (mysqld)
Status: "Server upgrade in progress"
Tasks: 28 (limit: 1106)
Memory: 685.0M
CGroup: /system.slice/mysql.service
└─4083 /usr/sbin/mysqld
我尝试过该门户网站和其他门户网站上建议的几种技巧，但都没有成功。