Caching APT updates

It’s bothered me for a while that all these VM’s are pulling down a lot of the same updates. As well as needlessly using some bandwidth, I’m hammering the update servers (that I don’t pay for) with the same requests over and over. I did briefly consider running my own mirror, but that’s not simple, plus I’d then be mirroring a heap of files in a complete repository that I’d never use. What I really needed was some sort of cache so once I’ll pulled down an update, it would hang around for a few days being available to other machines on the local network. Luckily, that exact thing exists - APT Cacher NG .