Over the past few weeks I have had several discussions around VMware features and technologies via twitter where someone asked a question or made statement around a VMware vSphere feature and the subsequent discussions seemed to shed some light on things people either didn’t know or had forgotten.

 

So my idea is to create a series of blog postings trying to cover compact VMware knowledge nuggets which I hope will show people some unknown features or things they need to think about around choosing features and maybe even get some good discussions going via the comments section.

Does excluding VMs from HA exclude them from admission control calculations?

This question was posted by fellow London VMUG attendee Ed Grigson a few weeks back via twitter as shown below

 

 

Due to my aiming to reattempt my VCDX defence soon I have been reading and learning as much as is possible and had come across the answer to this during my reading of Duncan Epping and Frank Denneman’s vSphere 5.1 Clustering Deepdive book and responded to Ed with the answer which is No. Even if it is disabled within HA, it is still included in admission control calculations. So be mindful of leaving machines lying around in your cluster as depending of your admission control policy this could have varying impacts on your ability to power on machines.