Failover Cluster Replication

I have recently been looking at Microsoft’s Failover Cluster Manager, used to create, validate and manage failover clusters running within Windows Server, i am hoping to put together a more extensive blog post in the future about the setup and configuration of this, but working backwards i guess im going to be looking here at Failover Cluster Replication.

This process is basically the replication of virtual servers from one failover cluster to another, be it on the same site or externally via a VPN or WAN link, the great thing about this however is that its all included in the box, there are no additional plugins or licenses required, so on with the actual steps involved with getting this done.

To begin with setting up Windows Server 2016 Hyper-V Replication, from within the Hyper-V manager console simply right click on the virtual machine you would like to replicate and choose “Enable Replication”.  If you are replicating two or from a failover cluster you need to specify the name of the Hyper-V Replica Broker server, this is a specific role that must be configured on the cluster server, we need to do this or you will receive the following error.

Setting up a replica broker is a relativity simple process, you need to open Failover Cluster Manager, right click on the cluster and select “Configure Role”

the wizard should open giving you options for the high availability roles, one of which should be “Hyper-V Replica Broker”

Create a name for the replica broker, along with an unused IP address.

When this is done, a computer object will be created within Active Directory for the replica broker network name.  At this point if you have any issues creating the broker object refer to Doug Symalla blog post regarding this, i had this issue adding the second broker on the second cluster, using the recommendations from Doug fixed the issue and i was able to start the broker and get replication working.

As an additional bit of configuration you also need to remember to enable a cluster as a replica server, to do this right click on your broker and select “Replication Settings”, here you need to enable the cluster as a replica server, choose if your going to use kerberos or certificate based authentication, and also the location your going to store your replica files, for added security you also have the ability to allow replication from specified servers, I tend to always use kerberos via port 80 as its relativity easy to configure and use.

You will then get a warning message regarding opening firewall ports, just make sure you check this as it can cause issues if the recommended settings are not applied.

You should now be able to head back to Hyper-V Manager and complete your replication wizard as you require, and it should start sending the initial replica.

On the target side within Failover Cluster Manager you should see your VM be created in an off state.

Once you have both brokers running within both clusters, it is then really just a case of configuring VM replication from within Hyper-V Manager.