Debian apt for installing software

Jorge

2023.10.02

2 mins to read

Home / Debian apt for installing software

apt commands

sources

located at

/etc/apt/sources.list

with debian repositories typically like

#------------------------------------------------------------------------------#
#                   OFFICIAL DEBIAN REPOS
#------------------------------------------------------------------------------#

###### Debian stable Main Repos
# deb http://deb.debian.org/debian/ stable main contrib non-free
# deb-src http://deb.debian.org/debian/ stable main contrib non-free

# deb http://deb.debian.org/debian/ stable-updates main contrib non-free
# deb-src http://deb.debian.org/debian/ stable-updates main contrib non-free

# deb http://deb.debian.org/debian-security stable/updates main
# deb-src http://deb.debian.org/debian-security stable/updates main

#------------------------------------------------------------------------------#
#                   OFFICIAL DEBIAN REPOS
#------------------------------------------------------------------------------#

####### Debian Main Repos
#
# Testing
deb http://deb.debian.org/debian/ testing main contrib non-free non-free-firmware

deb http://deb.debian.org/debian/ testing-updates main contrib non-free non-free-firmware

deb http://deb.debian.org/debian-security testing-security main

for extra repositories

/etc/apt/sources.list.d/SOME-SOURCE.list

content for example like this for unstable sources

#------------------------------------------------------------------------------#
#                   OFFICIAL DEBIAN REPOS
#------------------------------------------------------------------------------#

####### Debian Main Repos
#
# Unstable
deb http://deb.debian.org/debian/ unstable main contrib non-free non-free-firmware

pining sources

Gives different priorities to how packages are installed.

Look in /etc/apt/preferences.d/ for pinning options and definitions

documentation: https://linuxconfig.org/debian-pinning-howto and https://wiki.debian.org/AptConfiguration

Priority < 0: prevents the installation of a package version
\1 <= Priority <= 99: causes a version to be installed only if there is no installed version of the package.
\100 <= Priority <= 499: causes a version to be installed unless there is a version available belonging to some other distribution or the installed version is more recent
\500 <= Priority <= 989: causes a version to be installed unless there is a version available belonging to the target release or the installed version is more recent
\990 <= Priority <= 999: causes a version to be installed even if it does not come from the target release, unless the installed version is more recent
Priority > 1000: causes a version to be installed even if this constitutes a downgrade of the package

Package: *
Pin: release a=stable
Pin-Priority: 900

Package: *
Pin: release a=testing
Pin-Priority: 600

Package: *
Pin: release a=unstable
Pin-Priority: 500

example pinning definition

vim /etc/apt/preferences.d/50-debian-unstable

with content like:

# track testing, but allow packages from oldstable, stable and unstable

Package: *
Pin: release l=Debian-Security
Pin-Priority: 1100

Package: *
Pin: release a=testing
Pin-Priority: 900

Package: *
Pin: release a=stable
Pin-Priority: 600

Package: *
Pin: release a=unstable
Pin-Priority: 50

Package: *
Pin: release a=oldstable
Pin-Priority: 1