Rules to Better Hyper-V Clustering
To improve performance, it's a good idea to disable NetBIOS over TCP/IP on your cluster NIC and iSCSI NIC. NetBIOS isn't used in Server 2008 R2 clusters.Figure: Good example – the NetBIOS is disabled on the dedicated NIC's (iSCSI & Cluster Communications)
When you configure Hyper-V Clustering, each node will have upwards of 4 network adapters, some virtual and some physical. It is important to give these adapters meaningful names so you know what network adapter does what.Figure: Bad Example - It makes it hard to know what network adapter does what if you don't have meaningful namesFigure: Good example - As an example naming convention for network adapters on each nodeFigure: Good Example - It is easy to tell which network adapter does what when they have meaningful names
Having the network flooded with a virus is bad news – but it will be worse news if iSCSI traffic is going across the same network. This is why you should have your iSCSI or SAN traffic on a different VLAN.Figure: A managed switch allows VLANing Note: An even better and more expensive solution is purchase a separate Switch for each network (this example means 3 network adapters = 3 networks)
Being able to communicate with the domain is so important for Hyper-V and clustering. To protect yourself from Active Directory problems, you can completely separate your primary Active Directory domain.
Having a separate Active Directory domain will allow your Hyper-V machines to run without problems in the case that your main Active Directory domain fails for any reason.
When you setup a new Active Directory domain for your Hyper-V cluster, create a trust between to 2 domains.
It is important have the Live Migration and Cluster traffic on a separate network interface than the iSCSI or SAN traffic. If you do not you will see a performance hit while migrating virtual machines and the process will be a lot slower.
To specify the roles of each network adapter:
- Open the Failover Cluster Manager
- Expand the Networks section and you will see all of your network adapters listed
- Right click on the network that you are using for LAN and ISCSI and make sure that the following setting is selected
When setting up Failover Cluster Manager it is important that each Physical Machine, also known as a host or node be setup in an identical manner. This means each machine should be configured the same, with the same networks and same workloads running.
It is best practice to have your nodes only running the necessary features to run Failover Cluster Manager, leaving your VMs or other hosts not in the cluster to run everything else.
For this reason SSW recommends only running Failover Cluster Manager and Hyper-V roles on your nodes. It is also recommended that each node in the cluster is identical hardware, this is not strictly required but will assist in the ease of management.
Microsoft lists several recommended and supported network configurations. It is very important that you configure your Hyper-V Cluster with one of the supported network types otherwise you will have performance issues once you load up the cluster.Figure: Check you have one of the supported configurations listed on the >Microsoft Hyper-V Live Migration – Network Configuration page (this example has 3 networks) It may work fine initially on a non-supported configuration but when you start loading more Virtual Machines on to the cluster the performance will be degrade dramatically.
Don't log in and make manual changes to the clustered nodes.
When working with clustered environments it is important that settings be consistent across every node. The best way to handle this is through group policy.
Create a policy that you would like applied to each node of the cluster using the Group Policy Management .Figure: Bad Example - Do not manually change settings on each nodeFigure: Good Example - Changing settings through Group Policy keeps node settings the same
As Hyper-V Clustering requires some advanced networking technologies make sure you download the very latest drivers for all your network cards – don’t just rely on the out of box driver.