Failed Esxi

[handian08]

Hello,

If there are an esxi host failure, will the VM guest restarted before the guest migrate to other esxi host?

[Brisk]

Hi,

Assuming you have enabled  HA on your cluster and it is configured correctly, your VMs will be restarted on another host in the cluster.

Your guests will experience an unplanned shutdown, but there's no way to work around that. I mean, you could start using FT, but that is not an option for all of your VMs.

[handian08]

so vm reboot is needed? Can we avoid this?

[Brisk]

The only way to avoid that would be to use fault tolerance, but that does not scale to all the VMs in your cluster and has caveats that need to be taken into account.

It makes sense that all guest VMs experience a reboot, the underlying hardware experienced an issue so it's the same if your server is running virtual or physical

[markey165]

@handian08 - It isn't reall a "reboot". If an ESXi host fails unexpectedly, the VMs running on it will all fail unexpectedly too. What vSphere HA does then, is detect the failure, and "restarts" those VMs on other hosts.

The key thing here is the host failure is unexpected, so you can't prevent the VMs failing as well UNLESS as @Brisk suggests, you enable the Fault Tolerance feature on VMs that require higher levels of protection. This should be done on a per VM basis though, not for all VMs on the Cluster. For more info, see link

https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.avail.doc/GUID-02E5849B-6B02-453E-A...

Also be aware of limits and licensing

• https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.avail.doc/GUID-57929CF0-DA9B-407A-B....
• https://4sysops.com/archives/vmware-vsphere-6-7-fault-tolerance-the-ultimate-vm-protection/

HTH