I’ve written a detailed article on the topic of creating your own Ubuntu repository mirror using the Apt-Mirror utility. This article also includes leveraging an Apt-Cacher, for consolidating and saving bandwidth between multiple machines. We regularly make use of both of these utilities to maintain our Ubuntu and Debian installations in my workplace. We have maintained an internal repository to support our developers (all running Ubuntu!) for over a year. I also make use of an Apt-Cacher at home, which is a great boost to my limited bandwidth.
If you’d like to read my latest writeup on leveraging these two tools, see my article at Packt Publishing.