Hyper‑V Replica Deployment and Configuration. The use case for
Hyper‑V Replica is, do we have a faster solution than backup and
restore to protect our VMs? Well, if you know about ASR, you're thinking, well,
yeah, of course. We can do replication and failover.
Well, what if we weren't yet ready to adopt Azure?
And what if we didn't have the budget frankly to pay for that
disaster recovery infrastructure? Can we make do with features
that are built into Windows Server?
Well, of course,
the answer to that is yes. The feature is called Hyper‑V Replica, and some main
use cases here is mainly disaster recovery where you've got,
for instance,
multiple sites in your business and you want to protect the
VMs, the individual Hyper‑V virtual machines, against the
failure of not just the VM itself, but maybe there's an outage at the site level.
What happens is Hyper‑V Replica is an asynchronous replication channel.
Asynchronous means that when a change from the primary VM storage goes
over your communications media to reach the secondary,
the primary doesn't wait before sending another message.
In other words,
it doesn't wait for confirmation that the secondary has
ingested that bit of data and so on.
And so it's a bit on the lazy side as far as replication goes,
but it's faster,
you see. Another point I want you to understand is that with Hyper‑V
Replica, the secondary VM is offline, very much like an Azure Site
Recovery, as a matter of fact. I wouldn't be surprised if Azure Site
Recovery uses Hyper‑V Replica at least in part under the hood, because
remember, I said that Azure Site Recovery doesn't build your VMs until
you initiate a failover.
Similarly, with Hyper‑V Replica,
your secondary VM is off, it is turned off and unavailable, and it
only gets turned on when you initiate a failover,
you see. Another layer, we could say it's more for high
availability, is if we do a combination of failover clustering and
highly available Hyper‑V VMs with Hyper‑V Replica.
That way, you're combining both high availability via clustering and
disaster recovery with Hyper‑V Replica. That's pretty cool.
The takeaway I want you to know here for the exam, we you don't
have to go down that route very far at all.
You just basically have to know that when you're going to configure Hyper‑V
Replica for a VM that's in a Windows Server failover cluster,
you need to stand up a clustered role called Hyper‑V Replica
Broker. That's really the money, so to speak, that I want you to keep in mind.