I recently had to find which repository held the nginx package so I could enable the corresponding deb-src line in order to build the source code with apt. There are two ways to get this information. The first is with apt show <PACKAGE> e.g.: apt show nginx Then search for the line that begins APT-Sources: APT-Sources: http://mirrors.digitalocean.com/ubuntu focal-updates/main amd64 Packages Alternatively, can get the same information by using apt policy: # apt policy nginx nginx: Installed: (...
