Virtualization specialist and blogger Marcel van den Berg wrote a interesting blog post comparing high availability in VMware vSphere 5 and Windows Server 2012 Hyper-V with the title vSphere 5 versus Windows Server 2012 Hyper-V: high available VMs. In his blog post he mentions VMware Fault Tolerance, which I think it is a good feature but there are some things you have to be aware of.
VMware vSphere includes a feature called “Fault Tolerance” which allows you to run a hot-standby Virtual Machine on an other VMware vSphere Hypervisor host, which will take over if the primary Virtual Machine fails.
This is a great feature but it also has some disadvantages, because you have to sacrifice on scale and features.
- No Memory Overcommit (Dynamic Memory)
- Only 1 vCPU per Fault Tolerance Virtual Machine
- Maximum 4 Fault Tolerance VMs per host
- No Snapshots
- Maximum of 64GB RAM
- IPv6 is not supported in VMware FT
- Virtual Machine cannot be replicated with the vSphere Replication (SRM 5)
- No Hot-plug support for virtual devices
- No Dynamic Resource Optimization
Now Microsoft does not offer a Fault Tolerance feature in Hyper-V. But offers besides the Hyper-V Failover Clustering some great virtual guest clustering capabilities. But if you need true Zero Fault Tolerance the Microsoft partner Stratus Technologies offers a great solution (ftserver) with a lot less disadvantages.
Tags: ESX, Fault Tolerance, Hyper-V, Microsoft, Virtual machines, Virtualization, VMware, Windows Server, Windows Server 2012 Last modified: August 16, 2012
This really reads like an ad for Microsoft. “My car runs on gas. Now my bike doesn’t, but it is great because it has pedals. And some companies offer add-on motors for bikes.”
Well for me it is more like: “I have a car with wings… I don’t need them but your car doesn’t have wings ;)”