in DSS V7, it isn't possible anymore to change iSCSI options of a single Volume when the A-A-cluster is running - even if the volume isn't part of the cluster, not to mention if it has't a replication task assigned to.
As far as I remember, this was possible in DSS6.
Any idea, why this was changed from DSS6 to DSS V7? To me, there's no technical reason...
You can, just remove the Target from the the Resources in the Failover. So once this is a done you can detach the LUN from the Target and even delete the LUN after you remove the Replication task from the volume replication and remove the replication from the iSCSI logical volume in the volume manager.