Back

Using a UNC Network Share to Store Hyper-V Virtual Disk (VHD)

Performance tips when you must resort to SMB 20I previously covered the storage options for HyperV and described the many choices between direct...

3 min read
Published on Jun 27, 2008
Using a UNC Network Share to Store Hyper-V Virtual Disk (VHD)

Performance tips when you must resort to SMB 2.0

I previously covered the storage options for Hyper-V and described the many choices between directly attached or SAN storage, fibre channel or iSCSI, passthrough or VHD, Virtual SCSI or Virtual IDE, etc. If you missed that one, check it out atĀ http://blogs.technet.com/josebda/archive/2008/02/14/storage-options-for-windows-server-2008-s-hyper-v.aspx

However, I failed to mention in that post the option to store your VHD files in a CIFS/SMB file server share. This works fine with Hyper-V, although everyone is quick to remind me that this would be slower than block storage, if all else is the same. However, with faster IP networks (including 10Gb Ethernet) and the improvements in the SMB v2 protocol, you might be tempted by the added flexibility in your storage management.

How to do it

Storing your Hyper-V files on a file server is pretty straightforward. There are, however, a few of things that you need to implement this properly with Hyper-V.

First of all, remember to grant access to the computer account of the computer running Hyper-V. This is the DOMAINCOMPUTERNAME$ account, which you can use in the same way you would use a regular user account when granting permissions.

The second thing is that you need to do is use a UNC path when pointing to the file server. This is a path that looks like SERVERNAMESHARENAME. Using a mapped drive or mount point does not work with the Hyper-V Manager tool.

Last but not least, you need to do this at the computer running Hyper-V (or connected via Remote Desktop to that computer). If you try to use the Hyper-V Manager tool remotely, you will get an error message saying ā€œFailed to create external configuration store at ā€˜SERVERNAMESHARENAMEFOLDERNAME’: General access denied error (0x80070005)ā€. You can work around this by using constrained delegation to allow a workstation to work on behalf of the computer running Hyper-V.

Performance tips

Everyone agrees that, all else being the same, it’s faster to use an iSCSI LUN than an SMBv1 file share for your Hyper-V storage. There are, however, a few things you can do to improve your network performance for Hyper-V.

First, you can use a separate NIC on the server running Hyper-V for the file server traffic. This will help isolate the network traffic between the file server and the server running Hyper-V from other network traffic. To make sure there’s no VM traffic going through this NIC, do not connect it to the Virtual Switch.

You can also use a NIC with a TCP Offload Engine. These TOE NICs will improve your network performance and handle much of the work without additional burden to the CPU. This NIC could again be dedicated to the file server traffic.

Last but not least, consider upgrading your Windows file server to Windows Server 2008. The improved TCP/IP stack and the support for the new SMBv2 will significantly improve your file server performance.

These optimizations will actually work for any kind of TCP/IP traffic (except for the part about SMBv2 protocol enhancements, which are specific to a file server workload).

Step by step instructions…

Read the rest of the article @>Ā Jose Barreto’s Blog : Storing Windows Server 2008 Hyper-V files on a CIFS/SMB file share Need help storing your Hyper-V files on a file server or managing your environment?Ā Please check us out for yourĀ Managed ServiceĀ orĀ Microsoft ConsultingĀ needs.

This post has matured and its content may no longer be relevant beyond historical reference. To see the most current information on a given topic, click on the associated category or tag.

Related Posts

Azure Backup Needs Assessment | Plan Your Cloud Data Protection

Assessing Your Organization's Backup Needs for Azure Workloads

Learn how to assess your backup needs for Azure workloads, from compliance and recovery objectives to choosing the right tools for data protection and resilience.

Sep 26, 2025
6 min read
CUI Compliance and the Role of MSPs

Overview of CUI Compliance and the Role of MSPs

Explore the essentials of CUI compliance and how MSPs support DFARS, NIST 800-171, and ITAR requirements through secure IT services and expert guidance.

Sep 26, 2025
7 min read
Evaluating Data Retention Policies for Microsoft 365 and Azure

Evaluating Data Retention Policies for Microsoft 365 and Azure

Learn how to evaluate and manage data retention policies in Microsoft 365 and Azure to meet compliance, security, and operational needs.

Sep 26, 2025
6 min read
How MSPs Help Meet CUI Compliance Requirements

How MSPs Help Organizations Meet CUI Compliance Requirements

Learn how MSPs help organizations meet CUI compliance by offering expertise, secure environments, and ongoing support for DFARS and NIST 800-171 standards.

Sep 26, 2025
7 min read
MSP vs. In-House Support for CUI Data Management

MSP vs. In-House Support for CUI Data Management

Compare MSP vs. in-house support for CUI data management. Explore cost, expertise, compliance readiness, and which approach best protects sensitive government data.

Sep 18, 2025
8 min read
How to Plan an Effective Backup Strategy for Microsoft 365

How to Plan an Effective Backup Strategy for Microsoft 365

Learn how to plan and implement a backup strategy for Microsoft 365 that protects critical data in Exchange, SharePoint, Teams, and OneDrive against loss, ransomware, and compliance risks.

Sep 17, 2025
6 min read

Ready to Secure and Defend Your Data
So Your Business Can Thrive?

Fill out the form to see how we can protect your data and help your business grow.

Loading...
Secure. Defend. Thrive.

Let's start a conversation

Discover more about Agile IT's range of services by reaching out.

Don’t want to wait for us to get back to you?

Schedule a Free Consultation

Location

Agile IT Headquarters
4660 La Jolla Village Drive #100
San Diego, CA 92122