How to Upgrade Debian 10 Buster to 11 Bullseye Linux

Although while writing this tutorial the Debian 11 Bullseye was in RC1 state, however, it doesn’t matter you can use the steps given here even to upgrade Debian 10 Buster to 11, once you have the stable release…

We have tried to make the tutorial- how to upgrade Debian 10 to 11 as simple as possible. Here, we have simply changed the repository to perform the upgrading process. Well, while performing the steps given here we didn’t face any problems but we recommend you backup your system before following this article.

Step By Step Tutorial to Upgrade Debian 10 to Debian 11

1. System Update

The first thing we need to follow is to ensure that all the pre-installed packages are up to date and if any upgrade is available for them that must be installed. Open your command terminal and run the following command-

sudo apt update && sudo apt upgrade

Also, install-

sudo apt install gcc-8-base

Check the System’s current version.

cat /etc/os-release
Buster version check

2. Replace Buster repo with Bullseye

Next, we edit the source list file of Debian 10 and replace the existing repository addresses with Debian 11  ones:

sudo nano /etc/apt/sources.list

Disable all the existing entries for Buster by adding the # sign in front of each repo link.

#deb buster main 
#deb-src buster main  

#deb bullseye/updates  main  
#deb-src bullseye/updates main
Disable Buster Source repo sources list

Now, at the end of the file, copy-paste the following URL list.

deb bullseye main contrib non-free
deb-src bullseye-updates main contrib non-free

deb bullseye-security main
deb-src bullseye-security main
deb bullseye-backports main contrib non-free

Save the file by pressing Crtl+X, Y, and hit the Enter key.

Add bullseye repo on debian 10 buster

3. Run system update command:

To let the system recognize the newly added Repo URLs, run the system update command-

sudo apt update

If you don’t get any error after updating, then you can move further.

system update command

4. Command to fully upgrade Debian 10 to 11 Linux

Finally, run the system full system upgrade command that will upgrade all the existing packages to transit your old  Debian Buster system to the latest LTS Bullseye.

sudo apt full-upgrade

Follow the intermittent text wizards to set default things, when the system starts processing upgrades.

Give the system permission to download and install the required packages.

Note: Make sure the system screen doesn’t get locked during the upgrading process.

5. Reboot

Once the Debian 10 upgrading process is completed, reboot your system.

sudo reboot

6. Check the new system version

Now, let’s check which version we have on our system now, for that run-

cat /etc/os-release

You will see the output:

Check upgrader Debian 10 version
Linux 11 Bullseye system upgrade interface

Other articles-

7 thoughts on “How to Upgrade Debian 10 Buster to 11 Bullseye Linux”

  1. Well blow me down, learnt a command, please ignore my comment (and my ignorance) regarding shutdown -r as I was totally unaware that reboot can be used.

    This will save my fingers some wear in future, please accept my thanks 🙂

    • Wait for some time the process would get completed in the background. Or restart the system and run the upgrade command again.


Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.