Ade Malsasa Akbar contact
Senior author, Open Source enthusiast.
Tuesday, October 12, 2021 at 20:15

This tutorial will explain step by step to upgrade Debian Desktop version 10 Buster to version 11 Bullseye for your computer. We do this to the GNOME edition and the process downloads all the updates using the internet not CDROM. We will use command lines to proceed. We hope you can upgrade yours successfully including if you use Debian desktop choice other than ours. Let's upgrade!

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  • A computer with Debian version at least 10.0.
  • Enough free disk space.
  • Good internet access (fast and unlimited one is strongly recommended).  
  • Time and patience, upgrading needs much time and user interactions to accept some changes. 
  • Basic command lines skill.

(Debian 10 Buster, your operating system before upgrading)

First Step

To upgrade Debian, firstly we upgrade our current version to its latest by two commands:

$ sudo apt update
$ sudo apt upgrade --yes

Note! Doing this first step on a 6MB/s internet speed took about less than half an hour to us and around 400 MB download size.

Second Step

To upgrade Debian from Buster to Bullseye, like any previous versions, basically we need to change its Sources.list contents from buster to bullseye. In short, Debian's Sources.list is now simpler on Bullseye. Type everything correctly and remember all codes are in lowercase.

To edit the sources.list:

1. Open as administrator the file /etc/apt/sources.list.

2. Please notice three things you need to edit: the code buster mentioned in multiple lines, buster/security in one, and in the same line.

3. First, edit every mention of buster to bullseye correctly. See picture.

4. Second, edit buster/updates to bullseye-security. See picture.

5. Third, edit the URL address to See picture.

6. Save.

The text before:

deb buster main
deb buster main
deb buster/updates main

The text after:

deb bullseye main
deb bullseye main
deb bullseye-security main


Third Step

Once configured correctly, now we are ready to fully upgrade Debian to version 11 Bullseye by two commands:

$ sudo apt update
$ sudo apt full-upgrade --yes

Important! You should not see any error while doing the first, update command, otherwise correct your Sources.list then try again. 

Note! Doing this third step on the same internet access took us about 1 or 2 hours to finish and 600 MB download size.

Final Result

Once fully upgraded, now our Debian Desktop version is 11 codenamed Bullseye. As an addition, its GNOME user interface is upgraded to version 3.30 and is now utilizing Wayland by default. Congratulations!

(Debian 11 Bullseye, your operating system after upgrading)

Postinstall Notes

1. About size, our full upgrade of Debian GNOME 11 (vanilla installed) requires around one GB download and one GB disk space. Your upgrade experience might be more or less.

2. About time, our full upgrade requires around 2-3 hours.

3. About interruptions, our full upgrade experiences manual interventions two or three times to configure libc6 and some background services. Overall, we report that Debian 11 GNOME Desktop upgrade went smoothly.

4. After installation, we run commands to free disk space:

$ sudo apt autoremove 
$ sudo apt clean

Those freed around 600 MB disk space on our system.


Upgrades from Buster to Bullseye, Official Documentation

Upgrading Buster to Latest Point Release, Official Documentation

Debian 11 Release Notes

This article is licensed under CC BY-SA 3.0.