UMDS is an optional module of Update Manager. UMDS downloads patch metadata and patch binaries when Update Manager is installed in an air-gap or semi-air-gap deployment system and has no access to the Internet. The patch metadata and patch binaries that you download using UMDS must be associated with the Update Manager server so that Update Manager can patch the hosts and virtual machines in your vSphere environment.
Before you associate the UMDS patchstore depot with the Update Manager server, set up UMDS and download patches. For more information about installing, setting up UMDS, and downloading patches, see Installing, Setting Up, and Using Update Manager Download Service.
You can either use a portable media drive to transfer the downloads to the machine on which Update Manager is installed, or you can copy them to a Web server. You must then set up Update Manager to use a shared repository as a patch download source.