Hyper-V Clustering Server 2012 R2

[Disease]

I have 2 separate Hyper-V hosts, both running 2012 R2 and both the same machine spec and I am interested in clustering them to avoid single point of failure that I have now.

 

I am new to clustering and was wondering if you can still cluster them as is without affecting the VM's that are currently on them or is it a start from fresh process?

 

Any other advice regarding clustering Hyper-V on 2012 R2 would be very much appreciated.

 

Thanks

[tmcd35]

What storage are they connected to? It needs to be a Cluster Shared Volume to enable failover clustering on the Hyper-V hosts. An interesting alternative is to look at Hyper-V Replica which is quick and simple to set up and will replicate live VM's between the two servers so if one goes down they can be restarted on the other.

[Disease]

The VM's are stored on an iSCSI connected volume on our Nimble Storage Server.

 

Each host has it's own volume. Will take a look at Hyper-V Rplica.

[detjo]

Will take a look at Hyper-V Rplica.

 

"These are totally different solutions implemented to solve different issues. Failover cluster is for business continuity and H/V replica is for disaster recovery. They are complimentary to each other rather then competitive approaches. Both can failover VM from one physical node to the other but H/V replica does lose some data and does not do transparent failover (cluster does not lose data and does transparent failover from the other side). Also cluster does not put that heavy load on the network as it uses shared storage. H/V replica does not use shared storage so it has to synchronize all the changes over the network. So if you have very flexed RTO/RPO then you can simply skip using cluster (and maybe a backup app as well) and use only H/V replica. However if you want a guaranteed uptime and flexible recovery process you need all of them: replication, cluster and backup."

[From Technet]

[tmcd35]

You should be able to cluster with your set up but to be honest I'm not sure how to do it. You may need a Windows based header server to present the iSCSI volumes to the hosts. The theory is - the VHD's are stored on a shared volume - iSCSI - that windows knows is shared between more than one machine - Cluster Shared Volumes. The host accesses the VHD's through a ClusterVolumes folder in their C: drive.

 

You'll need to set up the CSV and then move the VM files into it. It should be possible without having to start from scratch, just a bit of work involved and resetting up Virtual Machines to run from the new location.

 

Clustering will give you automatic live failover. Hyper-V Replica is the easier to set up alternative. Replication is not live so VM's could be out of sync for a number of minutes. Also failover isn't automatic. You need to manually restart the VM on the new host after failover.