i recently opened a case (02055598) for my problem.
I have added the 3PAR VSS Hardware Provider and HP 3PAR CLI for most of my blades and it is working. But on one Host which holds the Exchange 2013 VM (with 16 TB LUN) the backup fails with:
01.02.2017 20:32:24 :: Unable to allocate processing resources. Error: There is no hardware provider for off-host backup detected. Snapshot failover is disabled.
I forced the usage of the hardware VSS to avoid that the microsoft VSS is used. Problem with that: Backup takes for hours and the merge too.
I moved 2 other VMs on that host on another LUN to check if the "hardware provider" is working at all. Well it is and these VMs are just backuped fine.
01.02.2017 17:31:21 :: Creating snapshot HP 3PAR VSS Provider on Hyper-V Off-Host Backup Proxy (mode: Veeam application-aware processing)
01.02.2017 17:32:23 :: Importing snapshot on offhost proxy Hyper-V Off-Host Backup Proxy
01.02.2017 17:32:56 :: Using backup proxy Hyper-V Off-Host Backup Proxy for D:\Hyper-V\VIRT-WSUS02\Virtual Hard Disks\VIRT-WSUS02.vhdx
The VSS Hardware Provider also does not start writing a log. So i think it really stops before it tries to use the VSS provider.
Someone has these big LUNs presented and can backup with Storage Snapshots?
I use an old version of the CLI and the VSS provider because it was tested fine.
CLI is: 22.214.171.124-MU1
VSS Provider is: 2.4.0