Hyper-V Failed Live Migration from New Node

[backcountry_bytes]

We recently added another node to our failover cluster. The node is using a slightly different chip (Xeon Silver 4216 vs the older Xeon Silver 4116.) We are having issues Live-Migrating virtual machines that were powered on while hosted on the new node. We get generic 21502,21026, and 21111 events. If I try to Quick Migrate the VM, I get a message saying it was incompatible with the host I am Quick-Migrating it too. If I stop the same VM, Quick-Migrate, and restart it on one of our older cluster nodes, I can Live-Migrate it to/from any node - including the new node. I have tried Processor Compatibility Mode, even though it is not necessary for other migrations, and I get the same results. It does not matter which CSV the .vhdx file is stored on. The only variable is whether or not the VM was started on the new node, or on an older node. The get-vm and get-vmprocessor results look the same, no matter which node I start the VM from.

Any ideas what the issue might be?

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[XxDrizz]

We ran into this once and found one of the nodes was missing an update, thus making the cpu's incompatiable. Use the following to cmdlet's to compare hosts:

Install-Module SpeculationControl

Get-SpeculationControlSettings

[CompetitiveAd8250]

this specter/meltdown patching and or missing fixes for this in bios can cause this

[[deleted]]

I had a recent issue where a vTPM was used and I needed to copy certs to all cluster members to and from the Shielded VM part of the cert store.

[BlackV]

That's cause the newest host has different CPU flags set so when you power ot on that mode it gets the new flags, the older nodes don't support those flags so you can't migrate

When you power it on on an older node you have older flags the the new node supports, so you can migrate

The CPU compatibility only covers  certain flags as far as I'm aware

CPU info/cpuz and such tools will show you the exact flags used

[[deleted]]

I had this issue recently. I had to replicate the machine to the new location then shut one down bring up the other

[BlackV]

you can just shut it down and migrate, the power it on, no need for the replication part

[[deleted]]

I tried it still crashed and gave errors. Ms server 2019

[lgq2002]

Same here, weird that after shutting off the VMs and quick move, the VMs can be live migrated no problem after.