apt-cacher-ng
When you manage more than a handful of Debian or Ubuntu systems, you quickly discover that downloading the same packages repeatedly from the internet is both wasteful and slow. Enter apt-cacher-ng, a caching proxy specifically designed for Debian package repositories. It sits between your local machines and the upstream mirrors, storing packages locally after the first download and serving them from cache for subsequent requests.
The beauty of apt-cacher-ng lies in its simplicity. Installation is straightforward: a single apt install apt-cacher-ng on a server, and you have a working proxy listening on port 3142. Client configuration is equally painless – you can either set the proxy in each machine’s apt configuration, or use the auto-detect feature if your network supports it. Once configured, every package fetched by any client is cached, dramatically reducing bandwidth usage and speeding up updates across your network.