Offhost proxy not working

[anicolai]

I have a three node cluster Windows 2012 R2 DataCenter, a Windows 2016 VM installed with Veeam B&R and finally a physical server installed with Windows Server 2016 with Veeam Repository and Hyper-V Offhost roles pushed to it. Hyper-V nodes and Veeam Proxy all have access to same Virtual Volumes (LUNs) on a StoreServ 8200. All four servers have 3Par CLI 3.2.2 MU3 and 3Par VSS 2.7.1 installed and configured. VSS appears to be working on all four servers.

I Veeam all Shared Cluster Volumes is configured for 3Par VSS with failback to software VSS.
I testjob will create a 3Par snapshot (confirmed) via 3Par Console, but its being mounted to one of the three Hyper-V hosts, not the Offhost Proxy.
Backup is now done over the network but read from the storage snapshot and, no surprise, has same performance as onhost backup.

If i edit my backupjob and force it to use offhost proxy, only the dedicated offhost proxy can be selected. Also i disable fall backup to onhost backup.
My backup job will now fail with offhost proxy available.

How do i troubleshoot this?

Hyper-V hosts, System Center Virtual Machine Manger and Veeam B&R server are all joined to the Active Directory and use same serviceaccount.
The physical server with repository and Hyper-V offhost proxy role is in WORKGROUP and use a local account with administrative rights. Can this play any role?

[foggy]

Hi Alex, versions of a Microsoft Hyper-V host and off-host backup proxy must coincide.