EV9 Backups in a Multi-Server Environment

Having now split Indexing and Storage on my EV9 systems how do I configure the backups?

In the previous single server model I ran a PowerShell to set/clear backup mode as part of the backup job. I guess I can update the script including all servers, but which server backup job do I tag it to? My concern is (if this is possible) having Indexes in backup mode but archiving occuring and vice-versa and any implications?

Am I on the right track, any suggestions.

Thanks,