最近几台服务器老是出问题，今天又发现Mysql挂了，无法重启，装的是Linux宝塔面版，直接查看错误日志
2021-02-04 13:26:09 10352 [Note] InnoDB: The user has set SRV_FORCE_NO_LOG_REDO on, skipping log redo
2021-02-04 13:26:09 10352 [Note] InnoDB: 5.6.50 started; log sequence number 0
2021-02-04 13:26:09 10352 [Note] InnoDB: !!! innodb_force_recovery is set to 6 !!!
2021-02-04 13:26:09 10352 [Note] Recovering after a crash using mysql-bin
2021-02-04 13:26:09 10352 [Note] Starting crash recovery...
2021-02-04 13:26:09 10352 [Note] Crash recovery finished.
2021-02-04 13:26:09 10352 [Note] RSA private key file not found: /data/server/data//private_key.pem. Some authentication plugins will not work.
2021-02-04 13:26:09 10352 [Note] RSA public key file not found: /data/server/data//public_key.pem. Some authentication plugins will not work.
2021-02-04 13:26:09 10352 [Note] Server hostname (bind-address): '*'; port: 3306
2021-02-04 13:26:09 10352 [Note] IPv6 is available.
2021-02-04 13:26:09 10352 [Note] - '::' resolves to '::';
2021-02-04 13:26:09 10352 [Note] Server socket created on IP: '::'.
2021-02-04 13:26:09 10352 [ERROR] InnoDB: Failed to find tablespace for table '"mysql"."slave_master_info"' in the cache. Attempting to load the tablespace with space id 4.
二、问题分析
1、这是innodb引擎出了问题。日志里提示到 Error: could not open single-table tablespace file ./data_dep/report.ibd ，通过这个报错信息可以判断出来，mysql丢失这个数据文件，或者是该数据文件损坏，当mysql启动的时候检测有问题，将进行恢复，提示正常恢复该数据文件，
三、解决办法
在mysql的配置文件my.cnf里找到 [mysqld]字段下，添加 innodb_force_recovery=6：
宝塔面版还是比较方便，管理、查看日志，修改都很方便。