Sorting VM backup order in a backup job

[sambsamb]

I have an environment where I'm trying to backup some 30 VMs on 5 different stand-alone Hyper-V 2012 R2 hosts. Is there a way that I can assign the order of VM backup inside the job? Veeam is configured with default settings to attempt 4 VMs concurrently. I'd like to ensure that Veeam attempts 4 VMs on different hosts as opposed to 4 VMs on the same host to get better bandwidth utilization at the source. Is there a way to configure VM backup order inside the backup job?
Thanks.

[foggy]

Sam, while you can specify the order in which VMs added into the job should be processed right when you adding them (the list is sortable), please keep in mind that in on-host mode, each of the hosts will act as the proxy and will process its VMs independently (hosts do not wait for other hosts to finish processing their VMs).

[sambsamb]

Thanks for the reply foggy, but when observing the job run, I see it processes all VMs on host1, then moves on to all VMs on host2, ... The VMs on each of these hosts are running off VHDs that are on local storage. So backing up 4 VMs from the same host concurrently makes a bottleneck at the source disk. How do I go about backing up 4 VMs concurrently - 1 from each of 4 different hosts, so that I would not have a bottleneck at the source disks?
Thanks again..

[tsightler]

If you go to backup infrastructure and select properties on the actual Hyper-V host you can set the maximum concurrent tasks for the on-host proxy (default is 4 I believe). If you set this to 1 on each host, and you have 4 host, and your repository is configured for 4 tasks, then you should get 1 tasks on each host concurrently, which sounds like what you are looking for.

In V7 you could also likely get the same behavior by right-clicking the Hyper-V host and selecting "Manage Volumes" and setting the maximum number of concurrent snapshots to 1 for each volume.

[sambsamb]

Excellent, that worked!

Just FYI, by changing the VM order in the backup job, the job would start VM1 on Host1, then error out on the next 3 VMs (from other hosts), then start VM2 on Host1 concurrently, then error out on the next 3 VMs (from other hosts), ...
So, I reconfigured each host for 1 concurrent backup, deleted the backup job, and recreated it with the default VM order (VM1 from host1, VM2 from host1, VM3 from host1, VM4 from host1, VM1 from host2, VM2 from host2, ...), and it worked as required. So, it's now backing up 4 VMs concurrently but 1 from each host. Throughput is much better than when I started above.

[foggy]

Just FYI, by changing the VM order in the backup job, the job would start VM1 on Host1, then error out on the next 3 VMs (from other hosts), then start VM2 on Host1 concurrently, then error out on the next 3 VMs (from other hosts), ...

This behavior doesn't look as expected, so I would appreciate if you could open a case with technical support and provide full logs for for investigation. Thanks.