"ORA-00245: control file backup failed; target is likely on a local file system" Backup fails on oracle 11.2 RAC database

On a multi node RAC database we were occasionally facing issue with RMAN backup.

RMAN> 2> 3> 4> 5>
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of allocate command at 04/25/2013 04:00:30
RMAN-03014: implicit resync of recovery catalog failed
RMAN-03009: failure of full resync command on default channel at 04/25/2013 04:00:30
ORA-00245: control file backup failed; target is likely on a local file system


The issue is intermittent and does not appear every time, and so we are not sure if this is actually some issue with configuration.

Reason:-

Oracle [Support Note ID 1472171.1] says that snapshot control file should be on shared location.

Solution:-

I logged into RMAN from each instance and checked the configuration

RMAN> show all;

RMAN> .
.
.
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '<oracle_home_dbs>/snapcf_DB01.f'; # default

Thus in different instances I found the value is different as snapcf_DB01.f/snapcf_DB02.f etc, also noticed "#default" at the end.

Though we did not have a shared location for oracle home, the path is similar on our servers, thus making rest of the path same except the DB01.f part.

So at the place of making it on shared location we just gave it a common name, by just giving following command from any one node.

RMAN> CONFIGURE SNAPSHOT CONTROLFILE NAME TO '<oracle_home_dbs>/snapcf_<SID>.f';

And running at one place makes the change working at all the instances. (its only default that can come different or else it should be same if you have common control files for all the instances).
Now not having the shared snapshot controlfile, but a same name is making it work and issue resolved.