Users Guide

10 Storage Solutions Guide
• Hyper-V does not restrict VMs from selecting disks that have been made a
clustered resource as a passthrough disk. If disks that have been made a
clustered resource are selected as passthrough disks for other VMs, data
may be inadvertently overwritten. Ensure that you select the appropriate
disk during configuration.
• A disk that is selected as a passthrough disk for a VM remains in the offline
state in the parent partition; however, if the disk is accidentally placed in
the online state, data corruption/loss may occur.
Disk Type Summary
Table 1. Disk Type Summary
Disk Type Advantages Disadvantages
VHD
• Hyper-V VSS Support for host-
based backup of VMs
• Greater portability - exported
VM can be easily
copied/moved to another
location
• Multiple VHDs may reside on
a single physical disk
• Supports VM checkpoints
• VHD size is limited to less
than 2 TB
• Additional processor resources
are required to manage I/O
requests to the VHD
Passthrough • Supports greater than 2-TB
LUNs
• Offers slightly higher
performance than VHDs
• Does not support Hyper-V VSS
for host-based backup of VMs
• Does not support Hyper-V VM
checkpoints
• Lacks portability of VHD (no
export)
• If booting from a passthrough
disk, an additional storage
location is required for the VM
files (XML, BIN, VSV)