Upgrading from one version of Debian to the newer version is a relatively simple process, but it is important to follow the steps outlined below carefully.

Here at Ibmi Media, we shall look into how to upgrade from Debian 11 Bullseye to Debian 12 Bookworm.

1. Update System Packages

The first step in upgrading is to update the system packages. This is done by running the following command in the terminal: 

$ sudo apt-get update

This will update the list of packages available in the repository.

2. Change "sources.list" to Bookworm

The next step is to change the "sources.list" file in order to point to the Bookworm repository. This can be done by running the following command in the terminal:

$ sudo sed -i 's/bullseye/bookworm/g' /etc/apt/sources.list

This will change all instances of "bullseye" to "bookworm" in the "sources.list" file.

3. Run the Upgrade to Debian 12 Bookworm

Once the "sources.list" file has been updated, the upgrade to Debian 12 Bookworm can be run. This is done by running the following command in the terminal:

$ sudo apt-get upgrade

This will upgrade all of the system packages to the latest version.

4. Upgrade Post-Installation Check

After the upgrade is complete, it is important to perform a post-installation check. This can be done by running the following command in the terminal:

$ sudo apt-get check

This will check for any errors or issues that may have occurred during the upgrade process.

5. Clean Up Obsolete Packages

Once the post-installation check is complete, it is important to clean up any obsolete packages. This can be done by running the following command in the terminal:

$ sudo apt-get autoremove

This will remove any packages that are no longer needed or used.

6. Troubleshooting Nvidia Drivers

If you are using Nvidia drivers, it is important to troubleshoot any issues you may be experiencing. This can be done by running the following command in the terminal:

$ sudo apt-get install nvidia-driver

This will install the latest version of the Nvidia drivers.

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