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Advanced : VMware HA Important Points

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VMWare HA Important Points



HA maintains the high availability of virtual machines when an event of host failure / isolation occurs by powering on them on running hosts.
Every host in cluster exchanges its heartbeat with other hosts to notify them that it is alive.
A host is declared as isolated when its heartbeat is not received within 12 seconds.
A host is declared as dead when its heartbeat is not received within 15 seconds, we can increase this duration to avoid false positives by defining an advanced setting das.failuredetectioninterval in vCenter.
If we set das.failuredetectioninterval to 60 seconds we can avoid false isolations, which means if an isolated host comes back within 60 seconds VM’s will continues to run on the same host, which means HA will never interfere.
When a host is declared as isolated after defined interval isolation response will be executed on that host.

If isolated response is set to “Leave Powered on” the vm’s will continues to run on the isolated, however if an…