CPU Options for Windows 11 VM

R

rbeard.js

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Aug 11, 2022
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What are you guys using for your CPU for windows 11 vms in proxmox?

My CPU is an Intel Xeon CPU E5-2698 v4 and isnt supported by microsoft for windows 11. I can alter the windows 11 ISO and get windows to install just fine. My CPU supports all necessary instruction sets for windows 11 25h2 so the only inhibiting factor is that Microsoft deemed that it's too old.

I have to set my CPU type to host as that the only way the VM is being passed the CPU capabilities properly. When I was trying to do an upgrade in place with qemu64 as my CPU type, it passed Microsofts ready for windows 11 tests. However, the install will fail as its not seeing support for SSE4.2 and POPCNT.
Windows update on a windows 10 machine vm using qemu will see the machine as update ready for windows 11 as well.

My issue Im running into is that even though windows 11 is installed and working fine with CPU set to host, windows update wont work properly because its seeing my unsupported CPU. I cant change to qemu64 as the system will just boot look because the capabilities like SSE4.2 and POPCNT are not being passed to the VM.

Is there another CPU type I should explore or an ability to make a custom CPU that I can pass all these capabilities properly and get the benefit of windows update seeing my CPU as supported so updates work as well? I attached my cpuZ results so you can see all the instructions Im trying to pass
 

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_gabriel said:
use the default "x86-64-v2-aes"
Click to expand...
Worked like a charm. Thank you


Random side question:
I updated the vm to windows 11 and figured I should update my virtio drivers as well. Bot my network is "gone" on the box. I can ping out but the box is reading as offline and I cant access webpages or remote manage it. If I set a consistent ping, windows will show the Ethernet up but if I stop the ping, it goes back down. Not doing anything fancy on this guy, just a standard linux bridge.
 
_gabriel said:
What do you mean ? what is "box" ?
Click to expand...
Box as in VM. My apologies

Looks like I can hit any and all things internal but cant resolve anything on the web. Ive disabled IPv6 and double checked all my settings on my nic and vm network device but still no luck.
Really odd that updating the drivers would cause me to lose web access. Everything was working like normal right before I did that. Rolling back to the previous version didnt fix it either.
 
It looks like I found a resolution.
I set the dns on my VM to 1.1.1.1 manually.
It was picking up on my dns settings properly but refused to resolve.
This machine is VLANd out so there might be a network rule or something I need to put in place so that DNS will resolve properly but They should be good to go for now!
 
The CPU you have is Broadwell. Windows 11 wants the CPU to support MBEC for VBS/HVCI/DeviceGuard, which did not appear until Coffee Lake. In between SkyLake and Kaby Lake was released, so it is quite old.

x86-64-v2-aes tricks Windows 11 into working and disables anything related to VBS as it can tank performance on older CPUs. The whole situation is rediculous and M$ is a pita.
 
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