The NSX Host Clusters upgrade upgrades the NSX VIBs on the ESXi host. Depending on the ESXi host and NSX version, an ESXi host reboot may be required when upgrading or uninstalling NSX VIBs from the ESXi host. Regardless of this, the ESXi host must enter the maintenance mode to complete the NSX VIBs change. The installed NSX VIBs will depend on the combination of the ESXi and NSX versions.
In a DRS enabled cluster, NSX will instruct vCenter to automatically perform the maintenance mode and evacuate hosts in a controlled fashion that allows the hosted VMs to continue to be running. If the VMs evacuation fails, the host will wait for manual intervention to reboot. In a non-DRS enabled cluster, both VM evacuation and ESXi hosts ...
