SQLServer2012映象主庫掛掉如何切換到映象備庫

主節點的主庫服務掛了，無法啟動。

強行啟動從庫。

在備庫執行：

USE master;   

ALTER DATABASE ec SET PARTNER FORCE_SERVICE_ALLOW_DATA_LOSS;

之後會恢復兩分鐘，備機的資料庫就能用了。

資料庫日誌：

The mirrored database "ec" is changing roles from "MIRROR" to "PRINCIPAL" because the mirroring session or availability group failed over due to FORCE_SERVICE_ALLOW_DATA_LOSS. This is an informational message only. No user action is required.

Starting up database 'ec'.

1 transactions rolled forward in database 'ec' (7:0). This is an informational message only. No user action is required.

0 transactions rolled back in database 'ec' (7:0). This is an informational message only. No user action is required.

CHECKDB for database 'ec' finished without errors on 2016-09-01 15:33:43.907 (local time). This is an informational message only; no user action is required.

如果主機恢復了就切回去。

--原來的主伺服器恢復,可以繼續工作,需要重新設定映象，第一次可能會報個錯

在備庫執行：

USE master;   

ALTER DATABASE ec SET PARTNER RESUME; --恢復映象   

ALTER DATABASE ec SET PARTNER FAILOVER; --切換主備

主備切換完成。