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vSphere 6 Fault Tolerance: Continuous Availability for vCenter Server

All the upgrades to the VMware flagship product lead to much better availability of services.

• By James Brown
• 03/09/2015

VMware Inc. just concluded its "One Cloud, Any, Application" event to promote newer software-defined solutions as part of vSphere 6. I was able to play with some of the vSphere 6 features during its beta life, and was quite surprised to find that some of the new vSphere 6 features will transform how the software-defined datacenter will be approached going forward. One enhanced vSphere 6 feature is vSphere 6 Fault Tolerance (vSphere 6 FT) for virtual machines (VMs).

vSphere 6 FT now has support for four virtual CPUs (vCPUs) and 64GB vRAM. In vSphere 5.5 FT, a VM was limited to 1 vCPU and the same amount of vRAM.

All this means is that the vSphere 6 FT upgrade offers a viable way to make vCenter a VM with continuous availability. There are other third-party solutions that similarly support a high-availability vCenter VM, but having a built-in, native solution may provide better integration. It also allows for user-friendly troubleshooting.

VMware also introduced its Fast Checkpointing technology that allows vSphere 6 FT VMs to remain in sync while powered on. Fast Checkpointing replaces Record-Replay, which was designed for just one VM. Fast Checkpointing allows vSphere 6 FT VMs to properly sync their bandwidth and instruction sets, making them more efficient and faster as compared to having them clustered.

In addition to Fast Checkpointing, there's also support for vStorage APIs for Data Protection (VADP). VADP enables backup for vCenter and other vSphere 6 FT VMs. There was no integrated backup solution in vSphere 5.5 FT, but version 6 works with your local or shared storage to allow the VMs to be stored independently of each other, further enhancing continuous availability for your vCenter VMs. This, of course, is just a taste of what's offered; there's lots more.

  vSphere 6 FT is easy to configure, once you've met the prerequisites:

1. Locate the vCenter VM to be used for vSphere 6 FT.
2. Right-click the chosen VM and select Turn On Fault Tolerance.
3. Check the Recent Tasks window, for a notification that the process is complete.
4. Locate and verify that two separate vCenter VMs have been created on separate ESXi hosts.
5. Check the VM in its summary window and ensure it's on separate storage datastores.
6. Right-click the chosen VM and select Test Failover.
7. Once the Failover test is successfully completed, vSphere 6 FT is operational for the vCenter VMs.

vSphere 6 FT will allow a lot of VMware engineers to have confidence in continuous availability for vCenter server VMs and other critical application VMs. VMware continues to whet our appetites for the general availability release date for vSphere 6. In the meantime, I'd suggest testing its features for yourself with itsHands-on Labs.