For you to be able to manage and configure vSphere Update Manager, you need to install a plugin for use with vCenter Server and enable it.
The vSphere Update Manage plugin has very limited support with vSphere 5.5 Web Client. All you can do is attach and scan hosts. This might change in the future releases, but for now, we need to use vSphere Windows Client for most of the tasks.
The following procedure will help you install and enable the vSphere Update Manager plugin for the vSphere Client: