iSCSI disk migration. How to execute on a running system?

Question

iSCSI

Good day gentlemen!
There is the following task:
Infrastructure:
2 physical servers with HP P2000 storage system connected via scsi. On the PVE servers, then 2 servers, one in each PVE in a Windows Failover cluster. In PVE, the tgt service is launched, the LUN is cut and the disk is given to the guest OS via iscsi because the storage system does not know how to iSCSI.

A new storage system with iscsi support has arrived, I want to move an iSCSI disk from the existing Windows cluster scheme to a new storage system, but I'm in doubt about how to implement this.
I thought to cut the necessary LUNs on the new storage system, connect a new iscsi disk in the iscsi initiator, add a new disk in the failover cluster manager, transfer data from the old to the new, disconnect the old one. But everything is beautiful in words. On a test bench without data, such a scheme rolls. On the disk, there are a lot of services spinning on the disk that do not know how they will behave with such manipulations.
Perhaps there is a more beautiful way to implement such a task? ideally there should be no service interruptions.

Answer 1

It won’t work without downtime, raise new servers and transfer services one at a time, there will be much less downtime

Answer 2

Think in this direction: https://social.technet.microsoft.com/Forums/ru-RU/...
But I don’t know what will come of it.

Answer 3

And by the way, connect iSCSI on your dedicated network, your switch, your wires, and of course, addresses.

Answer 4

On a test bench without data, such a scheme rolls

And the meaning of the manipulations on the test bench is now to doubt. Much more beautiful, and there are no other options, as it were.