Change Windows Hyper-V cluster to new network subnet

Question

Change Windows Hyper-V cluster to new network subnet

Alistair Russell 40

Hi,

We have the current Hyper-V cluster setup (IP addressing changed)

2 x sites

Site A 10.10.1.0/24

Site B 10.10.2.0/24

Both sites have a Hyper-V failover cluster using HP MSA SAN's for storage. Both clusters consist of two nodes. Server storage is direct connected to the SAN's. Both Hyper-V clusters have two virtual domain controllers on the cluster storage. There are no physical domain controllers.

They have been bought by another group who are changing the network equipment and IP subnets at both sites. Their plan is to unplug the current network equipment, plug in the new hardware and readdress both sites. Given that the current and new subnets will not coexist during this migration, I cannot see how we can readdress the failover clusters as the domain controllers will be unavailable.

Can anyone offer advise on the best way to approach this?

Thanks in advance

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Answer 1

Hailey Huong Bui 2,135 Independent Advisor

Hi Alistair. I think the key issue is that during the re-IP process, your clusters will temporarily lose access to Active Directory authentication if the domain controllers are offline.

To safely proceed, I recommend deploying a temporary domain controller (physical or virtual) that resides outside the affected subnets before starting the network changes. This allows cluster nodes and other services to authenticate during the transition. Once the readdressing and verification are complete, you can safely demote and remove the temporary DC. Alternatively, if you have recent backups of the virtual DCs, you could restore one to isolated hardware or use maintenance mode with static host file entries for authentication during the migration — though the temporary DC method is cleaner and more reliable.

I hope this information is useful.. If it is, don't forget to "Accept the answer" so that others could benefit too. Thank you .

Alistair Russell 40 Reputation points

2025-11-04T14:38:46.96+00:00
Thank you for the response.

After a call with the 3rd party network team, I have been advised that there will be no coexistent of current and new IP subnets/routing during the migration and no scope for having a physical domain controller out with the current subnets. So, my thoughts are as follows given that the biggest risk will be around getting the clusters back online:

Create a temporary DC on local storage on one Hyper-V node at each site (This will be done prior to the network changes, DC's will be addressed on the current subnets)

Physically connect both hosts to the new network equipment

Change the hosts physical addresses to new range

Change the address of the DC on local storage to new subnet IP on both nodes

Update the cluster IP to address on new range (Assume this would be successful as it could reach the DC on local storage)

Update the IPs of the virtual machines

Can you see any glaring issues with this approach?

Thanks

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Change Windows Hyper-V cluster to new network subnet

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