Please see the man page for sources.list(5)
for the gory details on the correct format of your sources.list file.
In general, you will have one or more lines pointing to resources available. Each line will start
wiTh either "deb" (binary packages) or "deb-src" (source code packages) followed by the base URL
for the repository, then the release name and finally the various branches of the release that you want to use.
deb http://mirror.ite.sfcollege.edu/debian jessie main contrib non-free
The above line says "you can get binary packages from http://mirror.ite.sfcollege.edu/debian -
and I want to get packages for Debian 8 (release name Jessie) and I want to use packages from
the main, contrib, and non-free branches".
Linux Mint - base URL http://mirror.ite.sfcollege.edu/mint
Don't forget to add the appropriate Ubuntu sources as well!
- tricia main upstream import backport
- ulyana main upstream import backport
Debian - base URL http://mirror.ite.sfcollege.edu/debian
Note that you can reference Debian releases either by release type (testing, stable, oldstable) or release name (stretch, jessie, wheezy).
- bullseye main contrib non-free
- bullseye-backports main contrib non-free
- bullseye-proposed-updates main contrib non-free
- bullseye-updates main contrib non-free
- buster main contrib non-free
- buster-backports main contrib non-free
- buster-proposed-updates main contrib non-free
- buster-updates main contrib non-free
- proposed-updates main contrib non-free
- stable main contrib non-free
- stable-proposed-updates main contrib non-free
- stable-updates main contrib non-free
- testing main contrib non-free
- testing-proposed-updates main contrib non-free
- testing-updates main contrib non-free
Ubuntu - base URL http://mirror.ite.sfcollege.edu/ubuntu
- bionic main universe multiverse restricted
- bionic-backports main universe multiverse restricted
- bionic-proposed main universe multiverse restricted
- bionic-security main universe multiverse restricted
- bionic-updates main universe multiverse restricted
- focal main universe multiverse restricted
- focal-backports main universe multiverse restricted
- focal-proposed main universe multiverse restricted
- focal-security main universe multiverse restricted
- focal-updates main universe multiverse restricted