[Users] Storage server

Dear All, At work, the network guys have come to a discovery that they have made a mistake in their network configuration... The Storage server that we use as ISCSI target in oVirt, is in the wrong VLAN, so the wrong IP address... What is the best way to make sure that all of our vms (40) that are using this scsi storage will come up again after the storage server has changed his ip? What are the best steps to be taken...? We are using oVirt Engine Version: 3.3.1-2.el6 Kind Regards, Koen