Dear Team,
I have VCenter 5.5 Server and esxi version are 5.0 and 5.5, i am trying to migrate VM from one cluster to another cluster on which EVC has been enabled, some of the host from my HP Gen 8 esxi host got migrated successfully to EVC enabled cluster which has gen 6, gen 7 and gen 10 host, but some of the VM from the same host failed to migrate giving below error.
Please help me understand the reason for few VM's from the same host got migrated and for few VM's showing vmotion failed error and kindly provide me the solution for resolving this issue.
Regards,
Rajesh
It may depend on when they were built and what OS they run. I have had this issue more commonly with Linux VM's than Windows. If you really ant to dig into it, you could check the NX/XD flag it is specifically calling out on various machines and see if they are different. This could give a hint. That's only if you really want to see what is happening. Actions required to remedying the situation is still to manually set the flag, hide the flag, power of and migrate, or build a new cluster with EVC mode set to Merom generation.
The CPUID mask of the VM is not compatible with what is needed to run on the target host. What is the EVC mode version that you are in?
Thanks for the the reply Greco
The one on which we have enabled evc is Intel Westmere generation.
Can you please help me understand does CPUID mask changes from VM to VM or how does VM gets it's CPUID mask and the reason from the same host few VM's got migrated and few are giving me error.
At a basic level VM's have their CPUID Mask set based on the physical processor they reside on. This is why EVC mode is required to move between different proc types. However, if for instance you set your EVC mode to Westmere generation, you cannot vMotion VM's from hosts which run Nehalem (or above) generation of processors.
In these cases all you need to do is schedule downtime for the VM and migrate it while powered off. Upon power on the NX/XD flags should set properly for the new host type and EVC mode. If this gives you issue (which it shouldn't), you can always hide the NX/XD flag (has to be powered off) which will allow it to migrate between hosts, but I wouldn't recommend going this route.
Thanks for helping me understand the CPUID mask, but still i am in one confusion how come other VM's from the same host moved to the EVC cluster and few VM's gave me error.
Are you specifically choosing the host they migrate to, or just the cluster and allowing DRS to pick the host for you? It is possible that the others migrated to a host with an EVC compatible proc, while the ones that are failing did not. If possible, you may want to consider changing the EVC mode to Merom Generation. This would require everything to be down though. You could just build a new cluster with EVC mode set at that level and then potentially vMotion everything to it while going back and forth in regards to adding hosts to it as you vacate them.
Yes Greco, i specified the host and VMotion happened for few VM's but not all.
It may depend on when they were built and what OS they run. I have had this issue more commonly with Linux VM's than Windows. If you really ant to dig into it, you could check the NX/XD flag it is specifically calling out on various machines and see if they are different. This could give a hint. That's only if you really want to see what is happening. Actions required to remedying the situation is still to manually set the flag, hide the flag, power of and migrate, or build a new cluster with EVC mode set to Merom generation.
Kindly refer this VMware KB: vMotion CPU Compatibility - Migrations Prevented Due to CPU Mismatch - How to Override Ma... it may help you to fix the issue.
Rgds
Kanishk
Yes Greco, even i had some doubt on OS version but the one which got migrated and the one which didn't are both same and that too Windows 2008 R2 64 bit and there is no difference on Hardware version of VM's. So now the only option i have to remediate is to create cluster and remove add host procedure or take a downtime of VM and power off and than check the NX/XD flags.
