Viewing the World in Binary

ESX – Insuff. resources .. for HA

Got this error when trying to start a new virtual machine. Bad News!! Cluster is running is out of memory.

No Problem!! Check “Allow virtual machines to be powered on even if they violate availability constraints” and you are good to go. This setting is found under Cluser Settings -> ‘Vmware HA’. This is a quick dangerous way to start additional VM’s.

You really have to make sure that the ESX hosts are using less than 70% of memory (This is purely my guestimate!!), it can be much less % in certain scenarios where servers tend to take big chunks at intervals. Quick check on the host mem % in cluster can be made under cluster -> hosts.

How to estimate how many VM’s I can run on my clustered infrastructure?

Simple!

  • Take the VM-host which has been assigned the most memory e.g 1Gb. Figure out which ESX-host in the cluster has least amount of memory (if all ESX hosts in the cluser have same Gbs of memory, then you dont need to figure out any thing) e.g the number is 24Gb.  So 24/1 = 24, if you have three ESX-hosts in the cluser then multiply 24*3 = 72 VM-hosts. 

To power on another VM-host without a sweat and keep ‘violate availability constraint’ enabled,  add another ESX-host to the cluster.

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October 24, 2008 Posted by | ESX-VMware | | Leave a comment