which of the following situations would result in VMware HA restarting virtual machines (Choose Two)?

Assuming the appropriate HA configuration options have been selected, which of the following situations would result in VMware HA restarting virtual machines (Choose Two)?

A.
An ESXi host in the cluster becomes isolated from the network

B.
An ESXi host in the cluster is put into Maintenance Mode

C.
A guest OS is manually powered off

D.
A guest OS fails

Explanation:
VMware HA provides high availability for virtual machines by pooling them and the hosts they reside on into a cluster. Hosts in the cluster are monitored and in the event of a failure, the virtual machines on a failed host are restarted on alternate hosts. If you select Enable VM Monitoring, the VM Monitoring service (using VMware Tools) evaluates whether each virtual machine in the cluster is running by checking for regular heartbeats from the VMware Tools process running inside the guest. If no heartbeats are received, this is most likely because the guest operating system has failed or VMware Tools is not being allocated any time to complete tasks. In such a case, the VM Monitoring service determines that the virtual machine has failed and the virtual machine is rebooted to restore service. Host network isolation occurs when a host is still running, but it can no longer communicate with other hosts in the cluster. With default settings, if a host stops receiving heartbeats from all other hosts in the cluster for more than 12 seconds, it attempts to ping its isolation addresses. If this also fails, the host declares itself as isolated from the network. When the isolated host’s network connection is not restored for 15 seconds or longer, the other hosts in the cluster treat it as failed and attempt to fail over its virtual machines. In a cluster using DRS and VMware HA with admission control turned on, virtual machines might not be evacuated from hosts entering maintenance mode. This is because of the resources reserved to maintain the failover level. You must manually migrate the virtual machines off of the hosts using VMotion.

3 Comments on “which of the following situations would result in VMware HA restarting virtual machines (Choose Two)?

  1. Lobke says:

    Hi ,

    Would the Master host not try to use the storage heartbeat first to determine if the host has failed or is only isolated from the network? The default action in version 5 for isolated hosts is ‘Leave VM on’ I believe. Only when the storage heartbeat cannot be located the Master host would asume the host failed and restart the VM’s on a different host. With this information I think the answer would be B and D.

    Any thoughts on this?

    referenced websites:
    http://www.yellow-bricks.com/2011/10/11/vsphere-5-ha-isolation-response-which-one-to-pick/

    “As part of the Isolation Response mechanism there are three ways HA could respond to a network isolation:
    Leave Powered On – no response at all, leave the VMs powered on when there’s a network isolation
    Shutdown VM – guest initiated shutdown, clean shutdown
    Power Off VM – hard stop, equivalent to power cord being pulled out

    When to use “Leave Powered On”
    This is the default option and more than likely…”


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