Users Guide

Using SMB/CIFS Shares in Hyper-V 53

Using SMB/CIFS Shares in Hyper-V

Hyper-V allows the use of SMB/CIFS shares (file shares) to host VM resources

such as ISO files or VHDs. Use of SMB/CIFS shares is not recommended due

to the performance limitations but there may be certain scenarios that might

benefit from their use. Consider the following when implementing SMB

shares in a HA environment:

• Best practice recommendation when using an SMB share in Hyper-V HA

environments is to make sure that the file share is also a clustered resource

so that it does not become a single point of failure in the highly available

environment.

• It is strongly recommended that the file share be managed by a cluster that

is separate from the Hyper-V Host Cluster. If the file server resources are

also hosted by the same cluster, there may be issues during failover

scenarios due to the file server resource not being online when the

dependent HA VM resources come online. This is especially true when the

same cluster node ends up owning the file server resource and the

dependent HA VM resource. For more information on configuring a file

server cluster, download the Microsoft document

Step-by-Step Guide for

Configuring a Two-Node File Server Failover Cluster in Windows Server 2008

from

microsoft.com

• When a VM that uses file shares is made a HA VM, the

High Availability

Wizard

may generate a warning that the file shares are not clustered

resources even when they are. This is known behavior and this warning

may be ignored.

• When accessing SMB shares from the Hyper-V hosts via UNC path, best

practice is to use the DNS name of the server hosting the share rather than

the IP address of the server hosting the share. For example, when mapping

to a shared folder

Share$

on server

FileServer.Domain.com

, make sure

that it is mapped using

\\FileServer.Domain.com\Share$

NOTE: Hyper-V does not support access file share via a mapped drive.