Clear Sky - Kuru

Description:

涉及的可能操作：

emca -repos recreate

emca -repos drop

emca -config dbcontrol db -repos recreate

emca -deconfig dbcontrol db -repos drop

使用这些命令管理Oracle Enterprise Manager Repository时，会遇到数据库出现hang或者无法进行连接的状态。只要emca进程执行完毕或者强行终止，数据库又恢复正常。在数据库出现hang时，如果做hanganalyze或者dump systemstate，发现没有明显的异常存在（这个还待进一步确认）。

Cause:

根据核查metalink的文档，发现有下面的解释：

Therefore it is important to understand that running these commands may/will cause the database to be unavailable during the time that the repository is being dropped and should not be run on a production database unless you are fully aware of the possible impact to database availability and have planned for this eventuality