Extension baselines contain additional software for ESXi hosts. This additional software might be VMware software or third-party software. You create host extension baselines using the New Baseline wizard.

Extensions can provide additional features, updated drivers for hardware, Common Information Model (CIM) providers for managing third-party modules on the host, improvements to the performance or usability of existing host features, and so on.

Host extension baselines that you create are always fixed. You must carefully select the appropriate extensions for the ESXi hosts in your environment.

To perform the initial installation of an extension, you must use an extension baseline. After the extension is installed on the host, you can update the extension module with either patch or extension baselines.


When applying extension baselines by using Update Manager, you must be aware of the functional implications of new modules to the host. Extension modules might alter the behavior of ESXi hosts. During installation of extensions, Update Manager only performs the checks and verifications expressed at the package level.


  1. Use the vSphere Web Client to log in to a vCenter Server Appliance, or to a vCenter Server system with which Update Manager is registered.
  2. In the Home view of the vSphere Web Client, select the Update Manager icon.
  3. From the Objects tab, select an Update Manager instance.
    The Objects tab also displays all the vCenter Server system to which an Update Manager instance is connected.
  4. Click the Manage tab.
  5. On the Host Baselines tab, click New baseline.
  6. Type a name, and optionally, a description of the baseline.
  7. Under Baseline Type, select Host Extension, and click Next.
  8. On the Extensions page, select individual extensions to include in the baseline.
  9. (Optional) Select an extension, and click Show Patch Details to see additional information.
  10. Click Next.
  11. Review the Ready to Complete page, and click Finish.


The new baseline is displayed in the Baselines pane of the Baselines and Groups tab.