Install this plugin on unlimited sites and manage them all from a central dashboard. This plugin communicates with your InfiniteWP Admin Panel.
The setup process is crazy, by far the most confusing I've ever encountered, and documentation is poor. I'm supposed to know how to setup a cron job to receive email updates? Where are these 302 errors coming from? If there's no clear help from InfiniteWP headquarters today, I'm sticking with ManageWP. In spite of ManageWP's issues, at least setup and use is comprehensible and support is quick.