linux下apt安装mysql导致mysql.user table is damaged

笔者在ubuntu下用 apt install mysql-server类似的命令安装mysql,

安装了最新版的mysql5.7,覆盖了操作系统内置的数据库mysql系统库。

最初启动mysql出错信息如下

service mysql start
Job for mysql.service failed because the control process exited with error code. See "systemctl status mysql.service" and "journalctl -xe" for details.

查看日志信息如下:

tail -100f /var/log/mysql/error.log

--27T23::.624983Z  [Warning] Changed limits: max_open_files:  (requested )
--27T23::.625097Z  [Warning] Changed limits: table_open_cache:  (requested )
--27T23::.803581Z  [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
--27T23::.805744Z  [Note] /usr/sbin/mysqld (mysqld 5.7.-0ubuntu0.16.04.) starting as process  ...
--27T23::.811597Z  [Note] InnoDB: PUNCH HOLE support available
--27T23::.811655Z  [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
--27T23::.811662Z  [Note] InnoDB: Uses event mutexes
--27T23::.811667Z  [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
--27T23::.811671Z  [Note] InnoDB: Compressed tables use zlib 1.2.
--27T23::.811676Z  [Note] InnoDB: Using Linux native AIO
--27T23::.812040Z  [Note] InnoDB: Number of pools:
--27T23::.812208Z  [Note] InnoDB: Using CPU crc32 instructions
--27T23::.814479Z  [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = , chunk size = 128M
--27T23::.826619Z  [Note] InnoDB: Completed initialization of buffer pool
--27T23::.829478Z  [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
--27T23::.842451Z  [Note] InnoDB: Highest supported file format is Barracuda.
--27T23::.851779Z  [Note] InnoDB: Creating shared tablespace for temporary tables
--27T23::.851863Z  [Note] InnoDB: Setting file './ibtmp1' size to  MB. Physically writing the file full; Please wait ...
--27T23::.887533Z  [Note] InnoDB: File './ibtmp1' size is now  MB.
--27T23::.888429Z  [Note] InnoDB:  redo rollback segment(s) found.  redo rollback segment(s) are active.
--27T23::.888458Z  [Note] InnoDB:  non-redo rollback segment(s) are active.
--27T23::.888905Z  [Note] InnoDB: Waiting for purge to start
--27T23::.939190Z  [Note] InnoDB: 5.7. started; log sequence number
--27T23::.939462Z  [Note] InnoDB: Loading buffer pool(s) from /var/lib/mysql/ib_buffer_pool
--27T23::.939724Z  [Note] Plugin 'FEDERATED' is disabled.
--27T23::.941332Z  [Note] InnoDB: Buffer pool(s) load completed at  ::
--27T23::.945460Z  [Warning] Failed to set up SSL because of the following SSL library error: SSL context is not usable without certificate and private key
--27T23::.945498Z  [Note] Server hostname (bind-address): '*'; port:
--27T23::.945538Z  [Note] IPv6 is available.
--27T23::.945566Z  [Note]   - '::' resolves to '::';
--27T23::.945589Z  [Note] Server socket created on IP: '::'.
2018-12-27T23:10:32.946334Z 0 [ERROR] Fatal error: mysql.user table is damaged. Please run mysql_upgrade.
2018-12-27T23:10:32.946376Z 0 [ERROR] Fatal error: Failed to initialize ACL/grant/time zones structures or failed to remove temporary table files.
--27T23::.946415Z  [ERROR] Aborting

解决方法如下:

https://serverfault.com/questions/789328/fatal-error-mysql-user-table-is-damaged-please-run-mysql-upgrade

vim /etc/mysql/mysqld.conf/mysql.cnf
[mysqld]添加以下内容
skip-grant-tables

/etc/init.d/mysql start --skip-grant-tables && mysql_upgrade
service mysql restart

如果以上方法无效，完整删除mysql重新安装

apt remove mysql*
rm -rf /var/lib/mysql
apt install mysql-server mysql-client
dpkg --configure -a

其他参考:

https://fatdba.com/2017/11/15/mysql-startup-error-error-fatal-error-mysql-user-table-is-damaged/

https://serverfault.com/questions/527422/mysql-upgrade-is-failing-with-no-real-reason-given