Oracle backup failed

When you set up a MSCS cluster (or FOC) it would aks you for a clustername, and IP. But this is as the name suggests, for the cluster, not for the application. It is for you to connect to for management purposes. Suppose you have a cluster with 2 Oracle Databases in 2 groups. If you'd like to run these one of these groups on each server (which I believe MSCS can do same as VCS) then how would people connect to the oracle group that is not co-located with the Quorum / Cluster name?

That is why you have an IP / Name in the group for the application you're clustering and NOT in some other unrelated group. Clustering is supposed virtualise the application so that it can move freely between nodes without the users having to worry about where it ir residing. In your config that is not achieved.

So, Cluster names/IPs are for the cluster, Database (oracle) names/IPs are for Oracle.

Hope that helps :)