Incremental backup of Hyper-V on to the tape..

Hi,

I have Hyper-V on windows 2008 R2 std ( 64bit).

Be 2012 on Windows 2008 R2 Std (64bit).

Now, I want to take backup of Hyper-V host having 20-30 VM on to the Tape Library(LTO5).

I have configured full backup with GRT enabled.

I have also configured incremental backup again to the tape. The following problem were occoring:-

1. Some incremental backup were taking long time.

2. Full VMs were taken but there is very few changes made in the VM.

Is this a known issue or I need to do some changes..

Please, help.

Thanks.