I'm trying to set up VMware HA for the cluster, and having trouble understanding how resource monitoring works. We overcommit memory as a general practice, so out provisioned memory is always ~1.5 higher on individual VMs.
So I created a cluster with 2 Hosts in it, and one was ~90% full in terms of memory (and I mean used memory, as provisioned was ~140%). Second host ran no VMs. Tried powering on one VM - and I got an error, saying that would make it impossible to tolerate one host failure.
Reading more, I found that when this happens and you disable the policy to prevent power on, VMware will not guarantee failover for all hosts.
- But does it mean that it will just not try if it thinks that there is not enough resources?
- Or does it mean that something bad might happen because memory usage will go over all available, and it'll have to start swapping?
- How does it make such decisions?