Debian Server 11 Bullseye Update Version Debian 11 (bullseye), 64-bit PC

Debian 11 (bullseye) release notes for 64-bit PC describe major distribution changes, upgrade guidance from Debian 10, and known issues. They also cover security-related defaults such as cgroup v2, yescrypt password hashing, and the new bullseye-security archive layout.

• Password hashing now uses yescrypt by default, improving resistance to dictionary attacks.
• Linux 5.10 allows user namespaces by default to improve sandboxing for browsers and container tools.
• Linux disables unprivileged bpf() calls by default; this reduces attack surface.
• The security archive layout changed to bullseye-security, which may require APT source and pinning updates.

• Persistent systemd journal is enabled by default.
• Improved support for alternative init systems such as OpenRC and SysV init.
• Open vSwitch upgrades may require changing /etc/network/interfaces from allow-ovs to auto.
• Exim 4.94 introduces taint handling changes that require configuration updates.
• FUSE 3 replaces FUSE 2 for some packages, which may require package adjustments during upgrade.
• Upgrades involving libgc1c2 may require running the upgrade twice.
• openssh-server may block new SSH connections for longer than usual during upgrade.

• Driverless printing and scanning are expanded with ipp-usb support for USB-connected devices.
• A new generic open command is available as an alias for xdg-open or run-mailcap.
• systemd defaults to cgroup v2.
• Kernel support for exFAT is included and used by default.
• Fcitx 5 is introduced as the new input method framework.
• Bazel is available in Debian as bazel-bootstrap.
• Persistent systemd journal storage is enabled by default.

• XFS no longer supports the barrier and nobarrier mount options.
• The rescue boot option is unusable without a root password unless SYSTEMD_SULOGIN_FORCE=1 is configured.
• 32-bit Xen PV guests are no longer supported.
• Some browser engines in bullseye are not covered by Debian security support.
• Intel microcode updates may break Wi-Fi on some CoffeeLake systems or cause boot hangs on some Skylake systems.
• redmine is not provided in bullseye.
• wicd is no longer available after the upgrade.
• lilo and Mailman 2.1 are removed from bullseye.

• Upgrade from Debian 10 (buster) only; direct upgrades from older releases are not supported.
• Before upgrading, back up /etc, /var/lib/dpkg, /var/lib/apt/extended_states, and package selections.
• Use apt upgrade --without-new-pkgs for a minimal upgrade, then apt full-upgrade.
• Record the upgrade session with script to aid troubleshooting.
• Update APT sources from buster/updates to bullseye-security and remove proposed-updates before upgrading.
• Install a linux-image-* metapackage after upgrading to keep receiving kernel updates.
• For OpenStack nodes, cgroup v1 may need to be restored via kernel parameters.
• For compatibility with buster, yescrypt can be changed back to sha512 in common-password.

• Debian 11 release notes
  https://www.debian.org/releases/bullseye/releasenotes
• Debian Installer for bullseye
  https://www.debian.org/releases/bullseye/debian-installer/

Product Information

Vendor: Debian

Product: Server

Product type: Software

Application category: Utilities

Platform: Linux

Variant: 11 Bullseye

Version: Debian 11 (bullseye), 64-bit PC

Vendor release date: Aug 31, 2024

Original release notes: View on vendor site

Published on updatealert.io: Jul 31, 2026