場景：兩台資料庫執行一段時間後發現集群掛了，一台服務正常，一台不正常。
日誌如下：
[error] innodb: attempted to open a previously opened tablespace. previous tablespace mysql/innodb_table_stats uses space id: 1 at filepath: ./mysql/innodb_table_stats.ibd. cannot open tablespace testdb/dr_actions which uses space id: 1 at filepath: ./testdb/dr_actions.ibd2013-11-18
21:25:25 a171e1a8 innodb: operating system error number 2
in a file
operation.
innodb: the error means the system cannot
find
the path specified.
innodb: if you are installing innodb, remember that you must create
innodb: directories yourself, innodb does not create them.
innodb: error: could not open single-table tablespace file ./testdb/dr_actions.ibd
innodb: we
donot continue the crash recovery, because the table may become
innodb: corrupt
the innodb log to it.
innodb: to fix the problem and start mysqld:
innodb:
1) if there is a permission problem in the file
and mysqld cannot
innodb: open the
file
, you should modify the permissions.
innodb:
2) if the table is not needed, or you can restore it from a backup,
innodb:
then you can remove the .ibd file, and innodb will do
a normal
innodb: crash recovery and ignore that table.
innodb:
3) if the file
system or the disk is broken, and you cannot remove
innodb: the .ibd
file, you can set innodb_force_recovery > 0
inmy.cnf
innodb: and force innodb to continue crash recovery here.
解決方法：
[mysqld]innodb_force_recovery=1
重啟資料庫服務
啟動成功後，在去掉該條記錄，再次重啟資料庫服務，即可。
可參看：
那是第一種情況，還有一種情況是兩端的資料不一致，導致無法啟動成功。
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