Hello!
This article http://msdn.microsoft.com/en-us/library/dd405549%28v=vs.85%29.aspx says:
"Hyper-V uses the Volume Shadow Copy Service (VSS) to backup and restore virtual machines (VMs).If the backup (volume snapshot) integration services are installed in the guest operating system, a VSS requester is installed that will allow VSS writers in the guest operating system to participate in the backup of the VM. "
"...
Backing Up the Virtual Machines
Hyper-V uses one of two mechanisms to back up each VM. The default backup mechanism is called the "Saved State" method, where the VM is put into a saved state during the processing of the PrepareForSnapshot event,snapshots are taken of the appropriate volumes, and the VM is returned to the previous state during the processing of the PostSnapshot event."
The other backup mechanism is called the "Child VM Snapshot" method, which uses VSS inside the child VM to participate in the backup....
...
Backup (volume snapshot) Integration Service is installed and running in the child VM.
The child VM must be in the running state."
Putting it all together: the backup integration services are installed in the guest operating systems by default (at least in Win2008-2012R2), but "The default backup mechanism is called the "Saved State" method,...",
wich does NOT use child vm snapshot creation. It means that checking the "Backup (volume checkpoint)" checkbox changes nothing (at least with running VMs) because the default method is "Saved state":
Q1: if the default method is "Saved state" and my VMs are running what should I do to take a backup by using"Child VM Snapshot" method?
Q2: is there any difference between a backup created by method 1 and method 2?
Thank you in advance,
Michael