What’s New in VMware vSphere 6.0: Multi-CPU Fault Tolerance

By | February 8, 2015

This post covers Fault Tolerance (FT) improvements available in vSphere 6. I am so happy that at last Fault Tolerance (vSMP supported) can be used to protect the business critical systems. Just for a quick reminder what are limitations of Fault Tolerance available in vSphere 4.0-5.5:

  • Only 1 vCPU per FT virtual machine.
  • Shared storage required.
  • Host CPU’s must be VMware FT capable and belong to the same processor model family. (+-400Mhz)
  • All ESX hosts in te VMware HA cluster have identical ESX versions and patch levels.
  • Virtual machines must be stored in virtual RDM or virtual machine disk (VMDK) files that are thick provisioned.

Are you a VMware newbie? No problem, please follow my post about Business Continuity provided by native VMware features.

So what's going to be changed in Fault Tolerance in vSphere 6? A lot and also very important features are as follow:

  • Up to 4 vCPUs (vSMP) and 64GB RAM VM.
  • Fast Check-Pointing has replaced the “Record-Replay”.

What’s New in VMware vSphere 6.0: Multi-CPU Fault Tolerance

  • Supports all Virtual Disk Type like Thick or Thin Provisioned.
  • Backup support with snapshots through VADP such NetBackup or vSphere Data Protection.
  • Supports vMotion of both Primary and Secondary Virtual Machine.
  • Storage redundancy such VDDK copies on separate datastores.
  • Para Virtualisation Devices are supported.

Max 4 Protected VMs or 8 vCPU per ESXi host (it depends on which reaches first)What’s New in VMware vSphere 6.0: Multi-CPU Fault Tolerance 2

Ok, we have discussed new features of Fault Tolerance in vSphere 6. What about requirements? There are as follow:

  • 10GB Network link for Fault Tolerance must be used
  • All machines protected are on a host running the same version of vSphere.
  • Dedicated virtual network VMkernel portgroups must be configured for FT logging.
  • 10-30% network overhead increase

As a conclusion, please follow Fault Tolerance comparison available in vSphere 5.5 and vSphere 6:

What’s New in VMware vSphere 6.0: Multi-CPU Fault Tolerance 3

At last, VMware provides a really good feature with RPO ~0 and RTO ~0 to be used for protection of Business Critical Systems (>1vCPU).

Author: Mariusz

Architect (~ 15 years experience based on passion...) with strong background as a System Administrator and Engineer. Focused on Data Center Solutions: Virtualization/Cloud Computing and Storage/Backup Systems. Currently living in Poland.