Using Hyper-V Replica Broker
If you use Failover Clustering, there is an additional requirement since a failover
cluster consists of multiple Hyper-V hosts. If a failover cluster is the target for Hyper-
V Replica, it’s important that the whole cluster can host the replicated virtual machine
and not just a single host. This means that the storage of the replica must be on an
SMB share or cluster-shared volume. Hyper-V Replica support in a failover cluster is
enabled by adding the Hyper-V Replica Broker role to the failover cluster. This will
require a name and IP address for the Hyper-V Replica Broker role, which serves as
the client access point (CAP) for Hyper-V Replica and will be the name used when
selecting the cluster as a target for a replica.
When enabling replication within a cluster, once the Hyper-V Replica Broker role is
added, the replication configuration is performed within the Failover Cluster Manager
tool. Once the configurations for replication are completed (which are the same as for
a stand-alone Hyper-V host), all hosts in the cluster will automatically be configured,
unless certificate-based authentication was selected, in which case each host needs its
own certificate configured.
You must configure the Hyper-V Replica Broker role in the cluster even if the cluster
is not a replica target (although this is highly unlikely, since in the event of a failover,
replication is typically reversed). This means that you always need the Hyper-V
Replica Broker role for a cluster that is participating in Hyper-V Replica in any way. If
the cluster is the replica target, the broker redirects the replication traffic because the
VM may move between hosts in the cluster. If the cluster is the source of the replica,
the broker enables authorization of the primary hosts at a cluster level, and of course
the replica is needed if the replication is reversed.
Once the Hyper-V Replica Broker role is created, you should modify its configuration
by selecting the Replication Settings action for the broker. Then enable the cluster as a
replica server and choose the various configurations, which are the same as for a
normal replica server, as shown in Figure 8.5. Once replication is enabled, you will
need to enable the required firewall exceptions on each host manually as this is not
performed by the broker configuration; an example is the Hyper-V Replica HTTP
Listener (TCP-In) firewall exception.