Chapter 5. Issues to be aware of for bullseye

For Intel GPUs available with Broadwell and newer, the Video Acceleration API (VA-API) implementation now defaults to intel-media-va-driver for hardware accelerated video decoding. Systems which have va-driver-all installed will automatically be upgraded to the new driver.

The legacy driver package i965-va-driver is still available and offers support up to the Cannon Lake micro architecture. To prefer the legacy driver over the new default one, set the environment variable LIBVA_DRIVER_NAME to i965, for instance by setting the variable in /etc/environment. For more information, please see the Wiki's page on hardware video acceleration.

Support for the barrier and nobarrier mount options has been removed from the XFS file system. It is recommended to check /etc/fstab for the presence of either keyword and remove it. Partitions using these options will fail to mount.

For bullseye, the security suite is now named bullseye-security instead of buster/updates and users should adapt their APT source-list files accordingly when upgrading.

The security line in your APT configuration may look like:

deb https://deb.debian.org/debian-security bullseye-security main contrib

The default password hash for local system accounts has been changed to yescrypt. This is expected to provide improved security against dictionary-based password guessing attacks, in terms of both the space and time complexity of the attack.

To take advantage of this improved security, change local passwords; for example use the passwd command.

Old passwords will continue to work using whatever password hash was used to create them.

Yescrypt is not supported by Debian 10 (buster). As a result, shadow password files (/etc/shadow) cannot be copied from a bullseye system back to a buster system. If these files are copied, passwords that have been changed on the bullseye system will not work on the buster system. Similarly, password hashes cannot be cut&pasted from a bullseye to a buster system.

If compatibility is required for password hashes between bullseye and buster, modify /etc/pam.d/common-password. Find the line that looks like:

        password [success=1 default=ignore] pam_unix.so obscure yescrypt
      

and replace yescrypt with sha512.

NSS NIS and NIS+ support has been moved to separate packages called libnss-nis and libnss-nisplus. Unfortunately, glibc can't depend on those packages, so they are now only recommended.

On systems using NIS or NIS+, it is therefore recommended to check that those packages are correctly installed after the upgrade.

The DNS resolver unbound has changed the way it handles configuration file fragments. If you are relying on an include: directive to merge several fragments into a valid configuration, you should read the NEWS file.

The rsync parameters --copy-devices and --noatime have been renamed to --write-devices and --open-noatime. The old forms are no longer supported; if you are using them you should see the NEWS file. Transfer processes between systems running different Debian releases may require the buster side to be upgraded to a version of rsync from the backports repository.

The addons for vim historically provided by vim-scripts are now managed by Vim's native “package” functionality rather than by vim-addon-manager. Vim users should prepare before upgrading by following the instructions in the NEWS file.

OpenStack Victoria (released in bullseye) requires cgroup v1 for block device QoS. Since bullseye also changes to using cgroupv2 by default (see Section 2.2.3, “Control groups v2”), the sysfs tree in /sys/fs/cgroup will not include cgroup v1 features such as /sys/fs/cgroup/blkio, and as a result cgcreate -g blkio:foo will fail. For OpenStack nodes running nova-compute or cinder-volume, it is strongly advised to add the parameters systemd.unified_cgroup_hierarchy=false and systemd.legacy_systemd_cgroup_controller=false to the kernel command line in order to override the default and restore the old cgroup hierarchy.

The following is a list of known and noteworthy obsolete packages (see Section 4.8, “Obsolete packages” for a description).

The list of obsolete packages includes:

With the next release of Debian 12 (codenamed bookworm) some features will be deprecated. Users will need to migrate to other alternatives to prevent trouble when updating to Debian 12.

This includes the following features:

When apt full-upgrade has finished, the “formal” upgrade is complete. For the upgrade to bullseye, there are no special actions needed before performing a reboot.

Without a pointing device, there is no direct way to change settings in the GNOME Settings app provided by gnome-control-center. As a work-around, you can navigate from the sidebar to the main content by pressing the Right Arrow twice. To get back to the sidebar, you can start a search with Ctrl+F, type something, then hit Esc to cancel the search. Now you can use the Up Arrow and Down Arrow to navigate the sidebar. It is not possible to select search results with the keyboard.