Oracle Backup - 1

Oracle Database Backup RMAN

1 day in the morning I was facing ORA-00245 and ORA-27037 during RMAN of (RAC with ASM) backup in office. We have license of Oracle Enterprise Edition of RAC. The surprising thing was getting ORA-00245 on node 1 and ORA-27037 on node 2 !!

Here,

ORA-00245: control file backup failed; target is likely on a local file system

ORA-27037: unable to obtain file status

So checked the lines above this ORA error, pointing me to some trace files. But was not able to find anything. I checked that ORA-27037 pointing me to get status of snapshot contorlfile on node 2 of node 1. Means snapshot controlfile of node 1 was required at node 2 !!

How it's possible? Checked inside metalink and got the architectural help which is obvious.

For RAC database, due to the changes made to the controlfile backup mechanism in 11gR2, any instance in the cluster may write to the snapshot controlfile. Due to this snapshot controlfile need to be visible to all instances. 

The snapshot controlfile MUST be accessible by all nodes of a RAC database, if the snapshot controlfile does not reside on a shared device error will be raised at the time of RMAN backup while taking snapshot of controlfile.

So, Follow below steps to your RAC environment.

RMAN> show snapshot controlfile name;

If you are not sing share storage ASM and using shared file system then use below command.

RMAN> CONFIGURE SNAPSHOT CONTROLFILE NAME TO '<shared_disk>/snapcf_<DBNAME>.f';

or if you are using ASM then got for below

RMAN> CONFIGURE SNAPSHOT CONTROLFILE NAME TO '+<DiskGroup>/snapcf_<DBNAME>.f';

This will now pointing to same shared location and will not give you backup related error.

Enjoy!!