Upgrade Debian 12 (Bookworm) to Debian 13 (Trixie).

To upgrade Debian 12 (Bookworm) to Debian 13 (Trixie), follow these steps carefully:

1. Update current system: Ensure that your Debian 12 installation is fully up to date.

    sudo apt update && sudo apt upgrade -y
    sudo apt full-upgrade -y
    sudo apt autoremove --purge -y
   

2. Edit sources list: Change references from Debian 12 (Bookworm) to Debian 13 (Trixie) in your sources list.

   Open /etc/apt/sources.list in an editor:

    sudo nano /etc/apt/sources.list
   

   Replace all instances of bookworm with trixie. If you’re using any additional sources in files under /etc/apt/sources.list.d/, change those as well.

   For example:

    deb http://deb.debian.org/debian trixie main contrib non-free
    deb http://security.debian.org/debian-security trixie-security main contrib non-free
    deb http://deb.debian.org/debian trixie-updates main contrib non-free
   

3. Update package list: Refresh your package list to reflect the changes.

    sudo apt update
   

4. Start the upgrade process: Begin the upgrade to Debian 13.

    sudo apt upgrade --without-new-pkgs -y
   

5. Perform the full upgrade: Upgrade all packages to the Trixie versions.

    sudo apt full-upgrade -y
   

6. Reboot your system:

    sudo reboot
   

7. Check the upgrade: After rebooting, confirm the system is running Debian 13.

    lsb_release -a
   

This should display Debian 13 (Trixie). Ensure everything runs smoothly and consider removing unnecessary packages with:

sudo apt autoremove --purge -y