Due to changes in Microsoft’s virtual machine generation counter specification that was introduced in the Windows 8 Release Preview and Windows Server 2012 RC, corresponding changes were also required in the virtual machine BIOS. Snapshots, checkpoints and VMotion actions of virtual machines with these versions of Windows are not compatible between ESXi hosts that have implemented different revisions of Microsoft’s virtual machine generation counter specification.

Snapshots and checkpoints of virtual machines with Windows 8 or Windows Server 2012 that are taken on a host running ESXi 5.0 Update 1 or ESXi 5.0 P03 will not resume on a host running later versions of ESXi ( ESXi 5.0 Update 2, ESXi 5.1, etc.) and the reverse.

VMotion is prevented between hosts running ESXi 5.0 Update 1 or ESXi 5.0 P03 to and from hosts running later versions of ESXi.

2015-11-05T15:01:32.804Z| vmx| I120: DUMPER: Group ‘VMGenCtr’ not found.
2015-11-05T15:01:32.804Z| vmx| I120: CPT: could not find group VMGenCtr
2015-11-05T15:01:32.804Z| vmx| I120: DUMPER: Item ‘AddrReg’ [-1, -1] not found.
2015-11-05T15:01:32.804Z| vmx| I120: DUMPER: Item ‘CtrCount’ [-1, -1] not found.
2015-11-05T15:01:32.804Z| vmx| I120: DUMPER: Item ‘CtrCountX’ [-1, -1] not found.
2015-11-05T15:01:32.804Z| vmx| I120: VMGenCtrCheckpoint: Failing restore from old Win8 checkpoint
[...]
2015-11-05T15:01:32.804Z| vmx| I120: [msg.checkpoint.migration.failedReceive] Failed to receive migration.
2015-11-05T15:01:32.804Z| vmx| I120: [msg.checkpoint.mrestoregroup.failed] An error occurred restoring the virtual machine state during migration.

Evidemment la solution proposée par VMware passe par un shutdown de la VM mais lors d’une grosse migration ça fait pas sérieux donc nous avons cherché un vrai workaround.

Sachant que cette feature est exclusivement utilisé par Active Directory Domain Services (pourquoi l’imposer à toutes les VM d’ailleurs ?!), nous avons chercher à la désactiver pour que le resume du vmotion sur l’ESXi de destination ne pose plus de problème. Et pas plus loin que dans une autre kb vmware, nous avons trouvé la solution:

The workaround involving adding the vmGenCounter.enable parameter to the virtual machine .vmx file may cause the new snapshot protection for domain controllers introduced in Windows 8/Windows Server 2012 to stop functioning.

Un petit coup de PowerCLI pour appliquer le setting à chaud :

Get-VM Windows2012R2|Get-View|%{$_.ReconfigVM((New-Object VMware.Vim.VirtualMachineConfigSpec -Property @{extraconfig=@((New-Object VMware.Vim.optionvalue -Property @{Key="vmGenCounter.enable";Value="FALSE"}))}))}

Et le vmotion passe en douceur

Hostd: [2010-07-23 23:13:26.774 FFC07E90 warning 'UserDirectory'] Group lookup failed for ‘ADMS\ESX Admins’

Après un rapide coup de google, voici l’explication dans le visdk41pubs :

By default, the ESX host assigns the Administrator role to the “ESX Admins” group. If the group does not exist when the host joins the domain, the host will not assign the role. In this case, you must create the “ESX Admins” group in the Active Directory. The host will periodically check the domain controller for the group and will assign the role when the group exists.

Il suffit donc de créer ce groupe et d’y ajouter les groupes/utilisateurs de votre choix pour qu’ils aient automatiquement le role “Administrator” sur l’ESXi :

Elle est pas belle la vie ?!