You can perform orchestrated upgrades of hosts or virtual machines in your vSphere inventory by using baseline groups. Baseline groups contain baselines for either hosts or virtual machines.
You can perform an orchestrated upgrade at the level of a container object or an individual object.
Orchestrated Upgrade of Hosts
Orchestrated upgrades let you apply upgrades, patches, and extensions to hosts in your inventory by using a single host baseline group.
If the baseline group contains an upgrade baseline, Update Manager first upgrades the hosts and then applies the patch or extension baselines. Because the upgrade runs first and patches are applicable to a specific host version, the orchestrated workflow ensures that patches are not lost during the upgrade.
Orchestrated Upgrade of Virtual Machines
You can use an orchestrated upgrade to upgrade the virtual machine hardware and VMware Tools of all the virtual machines in the vSphere inventory at the same time, using baseline groups containing the following baselines:
VM Hardware Upgrade to Match Host
VMware Tools Upgrade to Match Host
Upgrading the virtual hardware of the virtual machines exposes new devices and capabilities to the guest operating systems. You must upgrade VMware Tools before upgrading the virtual hardware version so that all required drivers are updated in the guest. You cannot upgrade the virtual hardware of the virtual machines if VMware Tools is not installed, is out of date, or is managed by third-party tools.
When you upgrade virtual machines against a baseline group containing the VM Hardware Upgrade to Match Host baseline and the VMware Tools Upgrade to Match Host baseline, Update Manager sequences the upgrade operations in the correct order, and VMware Tools is upgraded first.
During the upgrade of VMware Tools, the virtual machines must be powered on. If a virtual machine is in the powered off or suspended state before remediation, Update Manager powers it on. After the upgrade completes, Update Manager restarts the machine and restores the original power state of the virtual machine.
During the virtual hardware upgrade, the virtual machines must be shut down. If a virtual machine is powered on, Update Manager powers the machine off, upgrades the virtual hardware, and then powers the virtual machine on.