Adding a node to existing Windows Server 2012 R2 Hyper-V Cluster

I started working with Windows Server 2012 R2 cluster few weeks back. At the initial time, due to the lack of time – I started with a three node cluster and later made it as a four node cluster and now adding one more node. I thought of making a post on how to safely add a node to an existing production cluster.

I personally don’t encourage changing the Tyre while driving the car :D, however sometime the situation may demand it.

Before start

  • Ensure that the new server is on same patch level with other cluster nodes
  • Ensure that the server is on the same Firmware level with other cluster nodes
  • Ensure that Fail-over Cluster feature is installed
  • Ensure that Hyper-V role is installed and the Virtual Switch is configured with same name and settings as of other cluster nodes
  • Ideally, All cluster nodes should be identical – So I assume the new server is also having the same hardware as other cluster members
  • Ensure the Multipath software has installed as of other cluster nodes
  • Ensure that the Network interfaces are configured properly to meet the requirement for Hyper-V
  • Ensure that NICs dedicated for Live Migration, CSV, Heartbeat etc are able to ping to the respective IPs in other cluster nodes
  • Add an additional SAN disk of smaller size to be used along with validation test
  • Ensure SAN disks are visible in Disk Management of the new server. Just check, Don’t try to make it online.

    Check if DISKS are visible in Disk Management

    Check if DISKS are visible in Disk Management


I would definitely go through the validation tests every time I create/add nodes to the cluster. This will give us the confidence that everything is configured and working as expected before the activity starts. Since we are trying to add an additional node to the existing cluster, We should understand that validation test may interrupt the VMs hosted on other nodes as the CSV disks may go offline as part of the test. For this reason, I did assigned one more temporary disk and made it as a CSV so that we can select only this specific disk while performing the validation.

Go to Failover Cluster Manager – Nodes

Right click on Nodes and Select “Add Nodes”

Add node

Add node



Click next on the “Before you begin” page after reading :D.

On the “Select Server” page, Key In the server name and click on Add. Ideally, adding the node shouldn’t take more than ten seconds.

Adding the new node

Adding the new node


On the “Validation Warning” Screen, We need to choose the right option specific to running validation test. As I mentioned earlier, I prefer to run all test with a spare disk form storage which don’t have any production data. So select Yes.

Validation Warning

Validation Warning


Clicking Next will Switch on the Validation Configuration Wizard

The account used for running validation wizard should be a local administrator on all nodes.


Validation Wizard - Before Begin

Validation Wizard – Before Begin

The next screen is “Testing Options”. I prefer to run all tests. If you are re-running after identifying some issues, Its Ok to choose only that failed module by select “Run only tests I select”.


Testing Options

Testing Options

The next screen is important. We need to choose the right SAN disk which will be used for validation test. I already added a 1 TB disk and made it as a CSV disk – Name CSV-4. Chose the right disk and click on next.

Select the Storage which will be used for Validation test

Select the Storage which will be used for Validation test



In the Confirmation page, Have a look on the specific tests which are going to perform on each modules and click on NEXT



Click Next to start the Validation tests.

Validation Test in Progress

Validation Test in Progress


Once done, You can review the result by clicking “View Report”.

If any of the test got failed, the Wizard assumes that something is not correct, hence shouldn’t proceed with the next step with the blessing of wizard. However, Once you click on finish, You will go back to “Add Node Wizard”  where you will get Option to Run Validation test again or proceed without Validation test.


Validation Wizard - Result Summary

Validation Wizard – Result Summary

In my case, I am using NICs with trunking for HyperV Data traffic,  So while creating the Virtual switch – I haven’t assigned any IP to this interface which the validation wizard claims that its not good. As I am sure that this error is not going to make an issue, I am proceeding with the next Option.



In the next screen, Review the node to be added and click on NEXT.

Wait for the successful confirmation and that’s it.