When you upgrade virtual machines, the required downtime varies depending on the guest operating system.

The following procedures are involved in upgrading virtual machines:

Upgrade VMware Tools

Upgrade virtual hardware

During the VMware Tools upgrade, the virtual machine remains powered on. For Microsoft Windows operating systems, you must reboot the guest operating system at the end of the VMware Tools upgrade procedure. For Linux, Netware, and Solaris guest operating systems, no reboot is required at the end of the procedure.

When you upgrade VMware Tools, expect downtime as follows:

No downtime is required for vCenter Server.

No downtime is required for ESX/ESXi hosts.

You must reboot Microsoft Windows virtual machines at the end of the upgrade procedure, or later, to make the upgrade take effect.

On Windows guest operating systems, you must reboot the virtual machine a total of three times when you upgrade VMware Tools and the virtual hardware:

a

Power on the virtual machine.

b

Upgrade VMware Tools.

c

Reboot the virtual machine at the end of the VMware Tools upgrade.

d

Power off the virtual machine.

e

Upgrade the virtual Hardware.

f

Power on the virtual machine.

g

The Windows operating system detects new devices and prompts you to reboot the virtual machine.

h

Reboot the virtual machine to make the devices work properly.

During the virtual hardware upgrade, the virtual machine must be shut down for all guest operating systems.

Virtual Machine Downtime by Guest Operating System summarizes the downtime required by guest operating system and by upgrade operation.

Virtual Machine Downtime by Guest Operating System

Guest Operating System

Upgrade VMware Tools

Upgrade Virtual Hardware

Linux

No downtime

Downtime for shut down and power on of virtual machine

Netware

No downtime

Downtime for shut down and power on of virtual machine

Solaris

No downtime

Downtime for shut down and power on of virtual machine

Microsoft Windows

Downtime for reboot of guest operating system

Downtime for shut down and power on of virtual machine