The Debian Project currently estimates that Debian 11 (Bullseye) will reach EOL (end-of-life) sometime around July 2024 (approximately two months from now). Please upgrade all of your Debian 11 templates and standalones to Debian 12 (Bookworm) by then. For general information about upgrading, see Upgrading to avoid EOL.

There are two ways to upgrade a template to a new Debian release:

• Recommended: Install a fresh template to replace the existing one. This option may be simpler for less experienced users. After you install the new template, redo all desired template modifications and switch everything that was set to the old template to the new template. You may want to write down the modifications you make to your templates so that you remember what to redo on each fresh install. In the old Debian template, see /var/log/dpkg.log and /var/log/apt/history.log for logs of package manager actions.

• Advanced: Perform an in-place upgrade of an existing Debian template. This option will preserve any modifications you’ve made to the template, but it may be more complicated for less experienced users.

Note on Qubes 4.2

Please note that Qubes 4.2 does not support Debian 11 templates (see Supported releases and Qubes OS 4.2 release notes). If you have any Debian 11 templates on Qubes 4.2 (e.g., as a result of upgrading from Qubes 4.1), please upgrade them to Debian 12 immediately.

Note on Debian LTS

Debian releases have two EOL dates: regular and long-term support (LTS). See Debian Production Releases for a chart that illustrates this. Qubes OS support for Debian templates ends at the regular EOL date, not the LTS EOL date.