VMware Migration to new Cluster

[VMWhereAreYou]

Hi,

I have a 2 node vSphere cluster. I am migrating this to new infrastructure.

I want to retain my vSphere licensing.

Once I build my new infrastructure side by side the existing kit my plan was to:

• Use trial licenses on new kit
• Use vMotion to migrate VMs from cluster to cluster
• Reapply old licenses to new kit

Is this the best approach? It means no downtime with VMs and no new licenses to be purchased?

[a_p_]

From the licensing point of view, this is how it's usually done, i.e. run the new environment in evaluation mode until the old one is decommissioned.

However, in order to answer the question with vMotion you need to provide more information about the current, and the new environment. With just a new cluster managed by the same vCenter Server this shouldn't cause issue. Note that vCenter Server for Essentials (in case this is what you have licensed) will allow only 3 ESXi hosts.

André

[vXav]

I would add that the vCenter needs to be upgraded to a version that supports the version of ESXi installed on the new hosts.

If you have an Essentials Plus license you can still add 1 host, move the VMs to it, remove the old/empty one, and do the same with the second new host.

If you only have Essentials, vMotion is not supported. There is a little hack to that though (I did it to migrate our Essentials to Standard).

• Disconnect the host from vCenter
• Reset the evaluation period

CP /etc/vmware/license.cfg /etc/vmware/license.cfg.old
CP /etc/vmware/.#license.cfg /etc/vmware/license.cfg
/etc/init.d/vpxa restart

• Connect the host to vCenter with evaluation license
• vMotion your VMs

[VMWhereAreYou]

vCenter Standard + vSphere Enterprise on the hosts.

So I can add the new hosts into the existing vCenter and perform vMotion on all VMs?

Then, lastly, vMotion the vCenter server itself or rebuild it from scratch on the new infrastructure?

[a_p_]

So I can add the new hosts into the existing vCenter and perform vMotion on all VMs?

It's important, that the new hosts (version/build) are supported by the vCenter Server version!

Then, lastly, vMotion the vCenter server itself or rebuild it from scratch on the new infrastructure?

That's up to you. If vCenter is working as expected there's no need to rebuild it.

André

[vXav]

You can vMotion the VMs across clusters.

You can vMotion the vCenter itself. Although if your vCenter has a configuration that got messy with time it is sometimes cleaner to just rebuild it.

Again, make sure to upgrade your vCenter if your new hosts are of a higher version and that the config of your new hosts is coherent.

[a_p_]

Just one more quick note, although I assume that you are aware of this.

In order to be able to vMotion VMs, the hosts need to have compatible CPUs (EVC might be required).

André

[VMWhereAreYou]

Ok...

So I can't vMotion from AMD cluster to Intel cluster, but can vMotion from AMD cluster to AMD cluster (using EVC if different generations of AMD?)

If going from AMD to Intel, my only migration options then are cold migrations (downtime) - I suspect using VMWare convertor is the best approach?

Thanks

[vXav]

Or simply shut down the VM, vmotion it to the new hosts, power it back on. or unregister from old and register on new.

I think Vmware converter will take forever.

The idea of EVC is who can do more can do less but not the other way around.

So if the EVC level of your cluster is N, your VMs using instructions of CPU gen N-1 can hot vmotion. However a VM using instructions of CPU gen N+1 can't.

But if you are going from AMD to Intel (and vice versa) it doesn't matter, you can't hot vmotion.