snapshotting disk images with exchange db / volumes

I have been asking at technet about if I could snapshot an exchange db volume[1]. But it looks like that windows server backup is sort of doing the same. Creating vs image, and backup that one. However they truncated the exchange db log files after a succesful procedure. I was wondering if someone is doing this already. How does the guest freeze work exactly in windows (In linux it is quite clear no io is done). I assume that if the guest is invoking the vss service, and then you snapshot on the host environment. You have a snapshot with a vss image? So if you want to recover, you first need to 'roll back' to that internal vss image on the snapshot? [1] https://social.technet.microsoft.com/Forums/office/en-US/7818e7a5-3c09-4f... https://social.technet.microsoft.com/Forums/office/en-US/922ff22a-73d6-4b...