Requirements for backup Hyper-V 2012 VMS

Hello Everyone,

I have implemented Symantec Netbackup 7.6.0.1 to backup Hyper-V 2012 VMS. We have Hyper-V 2012 (RTM) 3.0 .

In some cases the virtual machines enter in saved state. Following Netbackup documentation for Hyper-V and after do some research, consolidate all information in a spreadsheet, see below...

Guest OS compatibility;
Integration Service is installed and updated;
Guest OS updated;
VM has only basic disk;
Shadow copy must be available to Hyper-V VSS and be located at the same volume;
VMs have at least 20% of free space on each disk;
VSS infrastructure is health and dos not present any issue;
WMI is OK;
At time of analysis, any peak of processing was presented;


I have worked with Netbackup, Backup Exec and Simpana and in all documentations, the type of backup (ONLINE vs OFFLINE) is a Microsoft designation and the backup application  can't decide about how to backup a virtual machine.

After check all pre-requirements present above 99% of issues related with vms enter in saved state when backup happens was solved.

But we still have some machines (4) enter in saved state, VMS is 2008 R2 with SP1 all VMS are in compliance with pre requirements table, BUT all VMS isn't compliance with item number 9. For testing this VMS I do a clone, because they are not in production the resources is dropping and the clones no more enter in saved state, so I use some .vbs scripts for stressing the VMS, and after stress, the VM enter in saved state. 

Have Microsoft some best practices for applying in Virtual Machine, like "20% of free resources when backup operation is run"...



Thank You!