Windows 2016 CPU Hot plug support.

[sienar]

Yep... totally overlooked I see. I ignored it cause of the comment below, now I see it's the same thing.

I don't think the other commenter was following the directions correctly or had a different problem. This fix has worked for me on multiple proxmox hosts on any Server 2016 VM. I believe Server 2019 does not have this issue, but I haven't tested it myself yet.

 

[Pourya Mehdinejad]

As I mentioned, everything is configured exactly as instructed in Redhat URl, but when increase the VCPUs, my windows VM get hung and shows bluescreen error.
Tried it with several machines over several hosts.

 

[sienar]

As I mentioned, everything is configured exactly as instructed in Redhat URl, but when increase the VCPUs, my windows VM get hung and shows bluescreen error.
Tried it with several machines over several hosts.

Pourya, I'm not sure what to tell you. This fix works for me on multiple Proxmox hosts and any Server 2016 VM. Either the steps aren't being followed properly or something else is different in your environment that's not being explained here.

 

[sienar]

As I mentioned, everything is configured exactly as instructed in Redhat URl, but when increase the VCPUs, my windows VM get hung and shows bluescreen error.
Tried it with several machines over several hosts.

Pourya, did you notice this comment in the redhat bugzilla thread? I hadn't noticed this one before but noticed it just now since I was skimming the thread to see if anything new had been posted. It indicates that CPU hotplug also requires greater than 2GB of RAM in the VM Guest. MY VMs all have greater than 2GB of ram so I never ran into this. BUT, I just tested this (by reducing the RAM on a test VM) and confirmed if a VM is configured for exactly 2GB or less it will fail to CPU hotplug. I've seen the VM either blue screen or just hang. Are your VMs greater than 2GB of ram?

Basically you'll need to apply the changes from my original post, and have at least 2049 MB of ram assigned to the VM to enable VCPU hotplug on Server 2016 guests.