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I inherited a Windows 2008R2 &nbsp;HyperV server that is hosting an Exchange server. &nbsp;During a power outage that depleted the UPS, the system reported that the .avhd file was corrupt and couldn't be read when the Exchange VM was being started. &nbsp;I restored from backup but was wondering why there is such a disparity between the original parent .VHD file and a number of .AVHD snapshots. &nbsp;The original .VHD file is dated Feb 2011 and there are &nbsp;four other .avhd files from various dates and then the most recent. &nbsp;I thought these were supposed to merge upon VM shutdown but I have no idea how this machine has been powered down in the past. &nbsp;Can a manual merge be performed and if so should it just be merged with the latest .AVHD file and the older ones deleted? &nbsp;The parent VHD is 23gb and the latest avhd is 173gb.
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I inherited a Windows 2008R2  HyperV server that is hosting an Exchange server.  During a power outage that depleted the UPS, the system reported that the .avhd file was corrupt and couldn't be read when the Exchange VM was being started.  I restored from backup but was wondering why there is such a disparity between the original parent .VHD file and a number of .AVHD snapshots.  The original .VHD file is dated Feb 2011 and there are  four other .avhd files from various dates and then the most recent.  I thought these were supposed to merge upon VM shutdown but I have no idea how this machine has been powered down in the past.  Can a manual merge be performed and if so should it just be merged with the latest .AVHD file and the older ones deleted?  The parent VHD is 23gb and the latest avhd is 173gb.

HyperV vhd file years older than .avhd snapshot

Hyper-V is a native hypervisor; it can create virtual machines on x86-64 systems and supersedes Windows Virtual PC as the hardware virtualization component of the client editions of Windows NT. A server computer running Hyper-V can be configured to expose individual virtual machines to one or more networks. Hyper-V Server supports remote access via Remote Desktop Connection. Administration and configuration of the host OS and the guest virtual machines is generally done over the network.