With Windows Server 2012 around the corner, I wanted to start sharing some of the capabilities that Hyper-V in Windows Server 2012 will start providing. Today I want to show you the Shared Nothing Live Migration. Just as the name implies, you can Live Migrate a VM from one host to another over just a network cable. Take note: Shared Storage and a Windows Cluster are no longer required to Live Migrate a VM from one host to another, but don’t tear down your cluster, or throw your SANs out yet! They still provide plenty of value, but now you can Live Migrate a VM to another host, or even another cluster if you need to.
Here’s a quick video that demonstrates Shared Nothing Live Migration:
As you can see, it really is pretty simple.
Now let me give you a few of the details about my setup. First, if you saw my Windows Server 2008 Hyper-V videos here, you may notice that I’m using the same server names that I was using for Windows Server 2008 videos. The reality is that I’m using the same hardware I used for those videos. That means the hardware is showing some age, but still runs Windows Server 2012 and Hyper-V, just not as fast as some of the modern day hardware. Second, the VM I was Live Migrating was about 16 GB in size and took 8 minutes, 40 seconds to Live Migrate from one host to another. About 2 GB per minute? As I said, I’m running on older hardware, I expect more current hardware to reduce this migration time significantly, but the reality is that Shared Nothing Live Migration still works. I’ve even seen VMs Live Migrated from one laptop to another with just a single network cable.
I recorded and timed three migrations; Shared Nothing Live Migration, Storage Live Migration, and Live Migration (in a cluster). All three migrations leveraged the same servers and virtual machine to migrate the VM. While I agree my timings were not “scientific”, I think these timings will give you some insight into the performance as you plan your deployments.
- Shared Nothing Live Migration took, 8 minutes and 40 seconds.
Remember, for this Live Migration the whole VM was copied over the network.
- Storage Live Migration took 5 minutes and 12 seconds.
This was a faster move than transferring the whole VM “over the wire”. Yes, my iSCSI SAN is “on the wire” as well, but I have two iSCSI NICs dedicated to the SAN.
- Live Migration took 11 seconds!
The same VM and hardware that took over 8 minutes to Live Migrate over the network took only 11 seconds to Migrate in a cluster.
I hope this information has helped, if you have any more questions, please let me know.
This session is one part of a whole series of screen casts around Hyper-V in Windows Server 2012, you can go this link to access the whole series.
Until next time!