Hyper-V 2012 R2 off host backup

Hi,

I'm currently setting up the backup environment for backing up our Hyper-V fleet. I'm running Netbackup 7.6.0.3 master server on windows 2008 R2. When the machine is taking the backup, while the snapshot running - the virtual machine has gone BSOD, not happening to every single VMs.

At the moment, I have installed a normal NBU client on each Hyper-V server. I'm looking to setup Hyper-V off host backup. Can someone please point me to a good documentation for setting up Hyper-V off host backup?

Thanks