Host updates are for maintenance releases. Software patches address critical security issues or urgent bug fixes. An update or patch can include a new build of firmware, an update of VMware Tools, or an update of the vSphere Client.

VMware provides the following tools for installing updates and patches to ESX/ESXi hosts:

vSphere Host Update Utility

Graphical utility for ESXi only.

vCenter Update Manager

For ESX and ESXi, automates patching and updates. See the vCenter Update Manager Administration Guide.

vihostupdate

Command-line utility for ESX and ESXi.

esxupdate

Command-line utility for ESX only. See the Patch Management Guide.