一。打开数据库alert日志，发现有报错

ERROR: failed to establish dependency between database RACDB and diskgroup resource ora.DATA.dg

二。上mos查看（是一个BUG,无害）

This error is harmless.

It is documented in the  internal Bug 8304720 "ERROR: FAILED TO ESTABLISH DEPENDENCY BETWEEN DB & DISKGROUP"

三。解决

$ srvctl modify database -d -a ""

我自己的库只有DATA和OCR两个磁盘组，所以执行一下命令：

srvctl modify database -d RACDB -a "DATA,OCR"