Using vSphere HA Orchestrated Restart an administrator places the most mission critical VM in the highest priority. After a host failure, the highest priority VM fails to restart while VMs in high priority restart. What would cause this to occur?
A. There are insufficient cluster resources.
B. Performance degradation VMs tolerate threshold is at default.
C. VMware Tools is not installed.
D. Proactive HA is disabled.
Correct is D
https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.avail.doc/GUID-3E3B18CC-8574-46FA-9170-CF549B8E55B8.html
https://docs.vmware.com/en/VMware-vSphere/6.7/vsphere-esxi-vcenter-server-671-availability-guide.pdf
VMs in Highest Priority should be first to Power on, them VMs in the High Priority ,so if the the VMs in the High Priority was powered on first ,we can say there is enough resources .
so something not working with the Highest priority configuration!
its could be the “Guest Heartbeat” Not Detected !! so if the Guest Heartbeat not detected — VM Monitoring not working , and VM Monitoring Need VMware Tools to be installed
For me also is A
Proactive HA not related.
VMware tools not related (vm should be powered on even without tools)
B is nonsense
The answer is A – VMware Tools is not installed. The algorithm of HA Orchestrated restart should be:
The above issues can be further fixed by using vSphere HA Orchestrated restart which performs a number of check to ensure Virtual Machines resources are secured and also focuses on Virtual Machine readiness.There are various checks performed like 1) VM has resources secured will be first check perform by vSphere HA ensuring that VM has CPU and Memory reservation requirements on one of the host in the cluster, 2) VM is powered On 3) Wait for VMware tools heartbeats ensuring that the operating system has started within the Virtual Machine and VMware tools application heartbeat is detected and at last 4) VMware Tools Application Heartbeat confirmation ensuring that the VM is ready and the services are now available.
if you don’t have VMware Tools installed, how you will be sure that Applications in the first rule are started up successfully, so you are able to proceed with power-on machines from rule 2 and etc.?
I think Proactive HA has nothing to do here, To me correct is A.