Resolved: Proxmox Cluster - Mixed CPU Question

[andif]

Hi all,

we are currently evaluating proxmox as an alternative to - guess what ?

Our small PoC environment consists out of three good old HP Microservers (Gen8).
System 1: 4 x Intel(R) Xeon(R) CPU E31225 @ 3.10GHz (1 Socket)
System 2: 4 x Intel(R) Xeon(R) CPU E3-1220L V2 @ 2.30GHz (1 Socket)
System 3: 2 x Intel(R) Celeron(R) CPU G1610T @ 2.30GHz (1 Socket)

All configuration went fine so far, really impressed by the ease of installation /configuration.

The issue we've identified (and I'm not sure, if this is can't be resolved at all) - live migration works fine between node 1 and 2 - but to node 3 can't be used at all:
when trying to start an ubuntu instance:
kvm: warning: host doesn't support requested feature: CPUID.01H:ECX.aes [bit 25]
kvm: Host doesn't support requested features

Found an article to resolve this issue to change the CPU type of the VM to "kvm64".

After this change both worked, boot and live migration. Question: What is the impact of choosing kvm64 in general? Will this option dismiss features available for other CPU types?

BR
Andy

 

[cheiss]

Hi,

After this change both worked, boot and live migration. Question: What is the impact of choosing kvm64 in general? Will this option dismiss features available for other CPU types?

Well, it normally only impacts performance, depending on the application. E.g. in your particular case, AES(-NI) is a instruction set extension used for accelerating common cryptography operations, esp. the AES cipher itself.
kvm64 is a very generic model w/o hardware acceleration extensions etc. to achieve maximum compatibility.

I'd suggest reading a bit into our admin guide, where we have also documented that more in detail: CPU Type

 

[andif]

Hi Christoph,

thanks a lot for the quick and comprehensive answer.
As I've assumed, setting up three old dogs with one very old dog delivers some disadvantages.

Ok - and one additional question.
Fiddled around with the live migration - this is very cool. But - I'm not able to configure to initiate an migration during shutdown.
According to some other articles this should be achieved by setting this option.

But it is ignored, the VMs are shutdown down.

Is there some else to be configured to achieve an automatic migration, when a cluster node is being shut down?

BR
Andy

 

[Azunai333]

This setting effects only HA (High Availability).

Are your VMs configured for HA?
Datacenter > HA

If you start to use HA this might interest you:
https://pve.proxmox.com/wiki/High_Availability