Choosing the Best Deployment Method for Implementing Hyper-V Network Virtualization

Hyper-V Network Virtualization, sometimes referred to as HNV, is a technology designed primarily for providers of cloud hosting. It helps cloud hosting providers to run multiple virtual machines (VMs) provide our clients with the same IP network design and topologies. Customers can easily move virtualized workloads to the cloud IaaS shared without having to make any configuration changes to the network layer.

One of the most common questions about Microsoft HNV is that the method should be used to distribute HNV. It 'best to use System Center Virtual Machine Manager 2012 R2, which is part of the System Center suite, or use the PowerShell cmdlets? Today we will see when using SCVMM PowerShell to distribute or HNV.

Microsoft offers two ways to distribute the configuration HNV on Hyper-V: System Center Virtual Machine Manager 2012 R2 and HNV PowerShell cmdlets.

You can choose one of two methods, but you need to understand what can go wrong if you deploy HNV using one of the methods above. I have seen many administrators implement virtual configuration using PowerShell cmdlets HNV HNV without knowing what could happen if a Hyper-V host is restarted due to a fault with the operating system.

And 'essential to understand that the method that you chose to implement the configuration HNV, both instruments use the classes AVN PowerShell to configure policies on high nature value of the target Hyper-V host. Each method has its advantages and disadvantages, which we will discuss shortly.

First we will cover the basic things you should know about SCVMM and then we will see the advantages and disadvantages when deploying configuration HNV using SCVMM and PowerShell cmdlets.

The initial thing to note with SCVMM is that it's a complex datacenter management product. If you want to deploy HNV configuration using SCVMM, you need to make sure you have:

• Sufficient working knowledge of SCVMM and its components.
• Working knowledge of how to create logical networks, VM networks, virtual subnets, and IP Pools in SCVMM.
• A strong understanding of cloud computing and its components
• Knowledge on deployments of gateway services through SCVMM.
• A good understanding of SQL Server.

If you've been using SCVMM for quite awhile and have working knowledge of cloud computing then you can use SCVMM as a deployment method for implementing HNV across Hyper-V Servers. But before you use SCVMM method, we want to cover the advantages and disadvantages associated with this deployment approach as explained below:

Advantages of Implementing HNV using SCVMM:

• HNV configuration is not lost after Hyper-V hosts restart. HNV configuration remains intact even after a Hyper-V host restart.
• SCVMM acts as a centralized tool to record all the actions performed on the Hyper-V hosts participating in the Hyper-V Network Virtualization.
• It is easy to manage HNV policies once deployed via SCVMM.
• Tenants can be created on the fly and without any downtime.
• Since Microsoft provides an Inbox HNV Gateway, it is easy to deploy a gateway service for multi-tenants via SCVMM.
• In SCVMM, the VMM server is responsible for automatically updating each VMM host with updated HNV configuration information as needed. Each VMM host will be provisioned with a subset of the entire address virtualization mapping table as needed based on the network configuration in use by the virtual machines hosted on each server.

Disadvantages of Implementing Hyper-V Networking Virtualization using SCVMM:

• It becomes hard to manage HNV configuration manually on Hyper-V hosts if the SCVMM connection is lost or the operating system holding SCVMM crashes for any reason.
• A misconfiguration in SCVMM could lead to downtime for all Hyper-V hosts and it could take a considerable amount of time to fix the issues.
• Since SCVMM uses SQL Server to store its configuration, any connection issues with the SQL database could cause SCVMM not to work, and the end result would be that you couldn't configure HNV for a new tenant.
• So far the earlier sections focused on the advantages and disadvantages of implementing HNV using SCVMM. Let's take a look at the advantages and disadvantages associated with the PowerShell deployment method.

Advantages of implementing HNV using PowerShell Cmdlets

• Suitable for small cloud hosting providers that host virtual machines for a few customers.
• Easy to make any HNV configuration changes if there are only two to three customer virtual machines running on the Hyper-V hosts.
• Deploying HNV using PowerShell cmdlets helps you learn how HNV works under the hood.
• In case you need to remove a HNV policy entry for a customer on a Hyper-V host, you can do so by executing a single PowerShell command, which is much easier than doing the same task in SCVMM.

Disadvantages of implementing HNV using PowerShell Cmdlets

• In the case of any maintenance activities — for example, applying windows updates — the HNV configuration is lost when a Hyper-V server restarts. This is the biggest disadvantage over the SCVMM deployment method. Virtualization administrators must create PowerShell scripts and run them to rebuild the HNV configuration after a Hyper-V host restarts. The HNV PowerShell script must be executed on all Hyper-V hosts that are participating in the Hyper-V Network Virtualization.
• It is hard to maintain the HNV configuration in a PowerShell script if new tenants are added.
• Things can become unmanageable when cloud hosting providers host virtual machines for multiple customers.
• Another disadvantage of deploying HNV configuration using PowerShell cmdlet is that there is not an easy way to configure a gateway service.

We have detailed some of the major advantages and disadvantages of the distribution of HNV configuration via SCVMM and PowerShell cmdlets, but when it comes to troubleshooting HNV on Hyper-V host, the best approach is to use the PowerShell cmdlets HNV. Therefore, we recommend initially trying to deploy a configuration HNV in a test environment using PowerShell cmdlets HNV. This not only helps to understand how HNV under the hood, but also helps to solve problems by using the PowerShell cmdlets HNV.

If you are unsure HNV PowerShell cmdlets that you can use to deploy a configuration HNV, please take a look at our Hyper V Network Virtualization Q & A article.

MCITP and a Microsoft MVP for Directory Services. He specializes in Microsoft technologies since 1994 and has followed the progression of Microsoft's operating system and software. In his spare time, he likes to help others and share some of his knowledge by writing tips and articles on various sites and to contribute to the solution.