Moving an ESXi host to a new vCenter Server

If you need to move an ESXi host to a different VMware vCenter Server, virtualization expert Rick Vanover explains how to perform this task.

There may come a time when you need to move a VMware ESXi host from one VMware vCenter Server to another vCenter Server. In production scenarios, I usually evacuate all of the virtual machines and put the ESXi host in maintenance mode to do this task. This can also be performed with virtual machines running on the ESXi host. Here are the steps to successfully complete this task.

First, you should remove the ESXi host from any Distributed Resource Scheduler (DRS)/High Availability (HA) cluster configuration, especially if there are running virtual machines on the host that need to stay online during the move. In this situation, I move the ESXi host to a folder that is not contained in a cluster and, therefore, no DRS/HA rules will be in play. This is done by selecting the Remove option within the vSphere Client (Figure A). Figure A

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There is some information and configuration loss when this is removed from vCenter; the primary issue is performance data and resource pools configured on the host directly are not retained.

On the other vCenter Server, the task is just as simple. You select the Add Host option in the cluster or folder that is to house the new ESXi host (Figure B). Figure B

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The new ESXi server will be inventoried in the new vCenter Server. All running virtual machines will stay online, and any host resource pools that were configured will be retained. You'll need to check resource pools that were configured on the previous vCenter Server cluster to make sure they are not under-provisioned now that one less host is providing resources to the cluster.

If the vNetwork Distributed Switch is in use, there are special considerations for this task. Read VMware KB 1029498 for details.

What tricks have you employed to move hosts between vCenter Servers? Let us know in the discussion.