How To Upgrade From Debian 10 to Debian 11


Debian 11 “Bullseye” was released on August 14th, 2021, and you may be now looking for upgrading your previous version, i.e., Debian 10 “Buster” to the latest version Debian 11 “Bullseye”.

This post will help you to upgrade your system from Debian 10 to Debian 11.



You must have an active internet connection to download packages for the OS upgrade.

Sudo Access

You must have root or sudo privileges to perform this OS upgrade.


Before upgrading your OS, take a full backup of important data files and configuration files. The backup may help us restore the system to its previous state if you face any issues after the upgrade.


  • Databases
  • Configuration files
  • Important application data files

Upgrade From Debian 10 to Debian 11

Test this Debian OS upgrade on development systems before upgrading the production or live systems.

Verify current version

Use the lsb_release -a command to see the current version of Debian.

Distributor ID: Debian
Description:    Debian GNU/Linux 10 (buster)
Release:        10
Codename:       buster

Update Debian 10

Update system to the latest version of the current operating system, i.e., Debian 10.10.0.

sudo apt update
sudo apt upgrade -y

Modify sources.list File

Rename current sources.list file.

sudo mv /etc/apt/sources.list /etc/apt/sources.list_bkp

Create a new /etc/apt/sources.list file.

sudo vi /etc/apt/sources.list

Add the below repository information to the sources.list file.

deb bullseye main
deb-src bullseye main
deb bullseye-security main
deb-src bullseye-security main
deb bullseye-updates main
deb-src bullseye-updates main

Update the package index.

sudo apt update

Preview upgrade

Use the apt list –upgradable command to quickly list what will be installed, updated, and removed during the OS upgrade process without affecting the system.

sudo apt list --upgradable


xz-utils/stable 5.2.5-2 amd64 [upgradable from: 5.2.4-1]
yelp-xsl/stable 3.38.3-1 all [upgradable from: 3.31.90-1]
yelp/stable 3.38.3-1 amd64 [upgradable from: 3.31.90-1]
zenity-common/stable 3.32.0-6 all [upgradable from: 3.30.0-2]
zenity/stable 3.32.0-6 amd64 [upgradable from: 3.30.0-2]
zlib1g/stable 1:1.2.11.dfsg-2 amd64 [upgradable from: 1:1.2.11.dfsg-1]

Upgrade to Debian 11

Now, upgrade all packages on your system to the latest version available on Debian 11.

sudo apt upgrade -y

During the upgrade, services installed on your system need to be restarted after the up-gradation of each service packages (ex. Apache, NTP), which may cause you service interruptions.

You can choose to restart automatically during the upgrade or manually after the upgrade. Here, I choose to do an automatic restart of services during the OS upgrade.

Automatic Service Restart
Automatic Service Restart

Also, you may be asked to choose what to do with a modified configuration file when there is a newer configuration file available for your system from Debian 11. You also have an option to compare both files and decide on it.

Modified Configuration File
Modified Configuration File
Modified Configuration File
Modified Configuration File

Do the distribution upgrade to complete the upgrade to Debian 11.

sudo apt dist-upgrade -y

Verify upgrade

Reboot your machine after the distribution upgrade.

sudo reboot

Verify the current version of the Debian operating system.

lsb_release -a


Distributor ID: Debian
Description:    Debian GNU/Linux 11 (bullseye)
Release:        11
Codename:       bullseye


That’s All. You have upgraded Debian 10 to Debian 11 successfully. Share your feedback in the comments section.

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