Upgrade to Debian 12 From Debian 11
Published on 2024-03-17
Upgrading From Debian 11 to Debian 12
First, update the packages index and upgrade:
sudo apt update
sudo apt upgrade
sudo apt dist-upgrade
Then, clean any residual packages and configuration files::
sudo apt autoremove
sudo apt autoclean
Check the current Debian version:
cat /etc/os-release
Make backups of your repository files:
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
sudo cp -r /etc/apt/sources.list.d /etc/apt/sources.list.d.bak
Once you have updated and cleaned your system, the next step is to upgrade the /etc/apt/sources.list file, as well as the files within your /etc/apt/sources.list.d folder.
In these files, you must replace all references from bullseye to bookworm, and from bullseye-updates to bookworm-updates.
Example of an updated /etc/apt/sources.list file:
deb http://deb.debian.org/debian bookworm main
deb-src http://deb.debian.org/debian bookworm main
deb http://deb.debian.org/debian-security/ bookworm-security main
deb-src http://deb.debian.org/debian-security/ bookworm-security main
deb http://deb.debian.org/debian bookworm-updates main
deb-src http://deb.debian.org/debian bookworm-updates main
Upgrade and clean the Debian distribution:
sudo apt update
sudo apt full-upgrade
sudo apt autoremove
sudo apt autoclean
Reboot:
sudo reboot
After rebooting, you can verify that the upgrade was successful by checking the Debian version information:
cat /etc/os-release
You should see output similar to:
PRETTY_NAME="Debian GNU/Linux 12 (bookworm)"
NAME="Debian GNU/Linux"
VERSION_ID="12"
VERSION="12 (bookworm)"
VERSION_CODENAME=bookworm
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
With the system successfully upgraded, you can now delete your old repository backup files to clean up your system:
sudo rm -f /etc/apt/sources.list.bak
sudo rm -r /etc/apt/sources.list.d.bak
With LEMP Server (for Debian 12 Upgrade)
If you are working with a LEMP (Linux / Nginx / MariaDB / PHP) server, it's essential to configure certain files before proceeding with the Debian distribution upgrade.
This example is based on Debian 12, Nginx, MariaDB 11.2, and PHP 8.3 configurations that were verified in March 2024.
Nginx:
To configure Nginx for Debian 12, follow these steps:
Open the Nginx repository file:
sudo nano /etc/apt/sources.list.d/nginx.list
Add the following line to the file:
deb [signed-by=/usr/share/keyrings/nginx-archive-keyring.gpg] http://nginx.org/packages/debian bookworm nginx
Nginx Documentation: Refer to the official Install Nginx on Debian documentation for more information.
MariaDB 11.2:
To configure MariaDB 11.2 for Debian 12, follow these steps:
Open the MariaDB repository file:
sudo nano /etc/apt/sources.list.d/mariadb.list
Add the following line to the file:
deb [arch=amd64 signed-by=/etc/apt/keyrings/mariadb-keyring.pgp] https://deb.mariadb.org/11.2/debian bookworm main
MariaDB Documentation: Refer to the official Install MariaDB on Debian 12 documentation for more information.
PHP 8.3:
To configure PHP 8.3 for Debian 12, follow these steps:
Open the PHP repository file:
sudo nano /etc/apt/sources.list.d/php.list
Add the following line to the file:
deb https://packages.sury.org/php/ bookworm main
Update an upgrade Debian distribution:
Then, proceed with the Debian distribution upgrade using the following commands:
sudo apt update
sudo apt upgrade