mysql重启失败 ib_logfile

重启mysql主库时遇到 log file /data1/webserver/mysql/data/ib_logfile0 is of different size 0 5242880 bytes

只要rm ib_logfile*即可。
ib_logfile类文件是innodb引擎的事务日志文件。看mysql文档
The ib_logfile's hold statements affecting innodb tables only. If a crash occurs they are automatically used to complete any innodb transactions that didn't complete before the crash.
就是说ib_logfile是用来当数据库异常关闭或崩溃时，用来自动恢复之前未完成 的事务。仅用于innodb