HA error code " Insufficient capacity in cluster to satisfy resource configuration in ESX Datacenter"

[TBROC]

Hi all,

I have some questions about how VMware HA determines if my cluster has enough resource to satisfy HA. I found something in Resource Management Guild : "For example, if you have a virtual machine with 1GHz CPU reservation and 1GB memory reservation and another virtual machine with 2GHz CPU reservation and 512MB memory reservation, the slot is defined as 2GHz CPU reservation and 1GB memory reservation. HA determines how many slots can “fit” into each host based on the host’s CPU and memory capacity."

Is it means that if i have three VMs in my ESX host1 : VM1 Reservation 1GHz&2GB

VM2 Reservation 2GHz&1GB

VM3 Reservation 3GHz&1.5GB

so, my "slot" will be a VM with 3GHz&2GB Reservation?

And if my ESX host2 don't have capacity for 3VMs with 3GHz&2GB, I'll receive some error code like " Insufficient capacity in cluster to satisfy resource configuration in ESX Datacenter" ?

Because I always receive this kind of error in my VI3 cluster (ESX Server 3.5 U2 & VC 2.5 U2) and I wanna know why it does.

Please identify if my interpretation is not correct.

Regards.

[weinstein5]

Welcome to the Forums - yes your interpretation is correct - that is exactly how slots are calculated -

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[TBROC]

So it means VMware HA use some "stupid" way to calculate HA capacity?

If I have only one VM with huge CPU or memory reservation, HA will think all VM being failed over need same huge reservation each, and of course, there won't be enough resource to satisfy HA capacity.

If my interpretation is correct, hope VMware will do something to improve HA capacity calculation.

Maybe some ESX Server or VC update version in the future ?