The problem may happen if 2 policies are using the same schedule/target RDS,
And therefore are trying to backup the same RDS databases at the same time.
The following errors may be logged in the Backup Log:
Info - Backup is agentless, managed by CPM Server
Info - Starting. Fired by schedule: weekly_schedule
Error - CPM Server identified this backup as orphaned: marking as failed
And
Info - Backup is agentless, managed by CPM Server
Info - Starting. Fired by schedule: weekly_schedule (retry 1 of 3)
Error - (database: dbname) can not take snapshot, db is in backing-up state
Error - (database: dbname2) can not take snapshot, db is in backing-up state
Warning - Finished kicking off snapshots, not all started successfully.
Warning - No Snapshots ran
Error - Backup Failed.
And this error during cleanup
Error,Failed to delete db snapshot (policy policy_name), delete operation failed
Error,Failed to delete db snapshot (policy policy_name), delete operation failed
Error,Failed to delete db snapshot (policy policy_name), delete operation failed
Error,Failed to delete db snapshot (policy policy_name), delete operation failed