Debian APT Update System

This article will show you how to update your Debian system with the APT package manager.
To update the list of Debian packages, use apt update.

george@dom:/media/george$ sudo apt update
[sudo] password for george:
Hit:1 http://deb.debian.org/debian sid InRelease
Hit:2 http://deb.playonlinux.com stretch InRelease
Hit:3 https://download.docker.com/linux/debian bookworm InRelease
Hit:4 https://packages.microsoft.com/repos/code stable InRelease
Hit:5 https://updates.signal.org/desktop/apt xenial InRelease
Hit:6 https://repo.steampowered.com/steam stable InRelease
Hit:7 https://dl.google.com/linux/chrome/deb stable InRelease
Get:8 https://apt.fury.io/wez * InRelease
Fetched 5,721 B in 7s (838 B/s)
884 packages can be upgraded. Run 'apt list --upgradable' to see them.

Use apt list to see which packages can be upgraded on your system.

george@dom:/media/george$ apt list --upgradable
7zip/unstable 24.09+dfsg-2 amd64 [upgradable from: 24.08+dfsg-2]
alsa-ucm-conf/unstable,unstable 1.2.13-1 all [upgradable from: 1.2.12-1]
alsa-utils/unstable 1.2.13-1 amd64 [upgradable from: 1.2.12-1]
anacron/unstable 2.3-41 amd64 [upgradable from: 2.3-40]

You can find out information on a package to upgrade with apt info <package name>:

george@dom:/media/george$ apt info 7zip
Package: 7zip
Version: 24.09+dfsg-2
Priority: optional
Section: utils
Maintainer: YOKOTA Hiroshi <yokota.hgml@gmail.com>
Installed-Size: 7,165 kB
Provides: p7zip, p7zip-full
Depends: libc6 (>= 2.34), libgcc-s1 (>= 3.0), libstdc++6 (>= 14)
Suggests: 7zip-standalone, 7zip-rar

To start upgrading the system, use sudo apt upgrade (sudo runs the application with root privileges needed to modify the system files).
It will display a list of packages that will be updated and the space needed on the root disk.

george@dom:/media/george$ sudo apt upgrade
[..]
Summary:
  Upgrading: 853, Installing: 55, Removing: 0, Not Upgrading: 31
  Download size: 2,103 MB
  Space needed: 527 MB / 5,865 MB available

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