Debian Server 13 Trixie Update Version Debian 13 (trixie)

Debian 13 (trixie) release notes cover the upgrade from bookworm, new architecture support, and major platform changes such as 64-bit time_t, OpenSSH DSA removal, and /tmp moving to tmpfs. They also list important upgrade cautions, deprecations, and known severe bugs.

• arm64 hardening against ROP and COP/JOP attacks using PAC and BTI when supported by hardware
• OpenSSH no longer supports DSA keys; DSA is considered weak and should be replaced with stronger key types
• openssh-server no longer reads ~/.pam_environment by default because of its security history
• Removed git-daemon-run and git-daemon-sysvinit packages due to security reasons
• Debian notes limited security support for some browser engines, especially qtwebengine-based applications

• Improved package versions across the distribution, including major updates to core components such as Apache, Bash, OpenSSL, systemd, and the Linux kernel
• apt full-upgrade may fail with 'Could not perform immediate configuration'; retrying with APT::Immediate-Configure=0 is documented as a workaround
• dpkg warnings about being unable to delete old directories during usrmerge finalization can be safely ignored
• Network interface names may change after upgrade on some systems, especially with the i40e driver or _SUN ACPI exposure
• RabbitMQ cannot be directly upgraded from bookworm; the database may need to be wiped and recreated after upgrade
• MariaDB major version upgrades require a clean shutdown before upgrading to avoid startup failure
• OpenLDAP TLS support now comes from OpenSSL instead of GnuTLS, changing available options and behavior
• Samba AD DC functionality and VFS modules were reorganized into separate packages
• libvirt packaging was overhauled into more granular binary packages

• Official support for riscv64
• HTTP Boot support for Debian Installer and Debian Live Images on supported firmware
• Spell-checking support in Qt WebEngine browsers using Hunspell BDIC dictionaries
• curl and libcurl now support HTTP/3, and curl ships wcurl as a wget-like download helper
• 64-bit time_t ABI transition on all architectures except i386
• Debian now ships debian-repro-status and rebuilderd for reproducible build tracking
• Plasma 6, KDE Frameworks 6, and updated KDE Gear applications
• Cloud images for AWS, Azure, OpenStack, and plain VM deployments

• Interrupted remote upgrades over SSH can leave bookworm systems inaccessible until OpenSSH is updated first
• i386 is no longer supported as a regular architecture and should not be upgraded to trixie
• armel is the last release supported in trixie and has limited hardware support
• mipsel and mips64el architectures have been removed
• A too-small /boot partition can cause the upgrade to fail; Debian recommends at least 768 MB and about 300 MB free
• On upgraded systems, /tmp becomes tmpfs after reboot, which can hide existing files in /tmp
• /etc/sysctl.conf is no longer honored by systemd-sysctl
• Ping no longer runs with elevated privileges and depends on net.ipv4.ping_group_range behavior
• Some systems may lose network connectivity after reboot due to interface name changes
• Dovecot configuration is incompatible with previous versions and should be ported before production upgrade
• strongSwan is migrating to charon-systemd; existing charon-daemon setups need migration planning
• Bacula database schema upgrade can take a very long time and requires substantial extra disk space
• Known severe bugs include issues in apt, linux, grub-efi-amd64, kmod, python3.13, and others

• Upgrade path is supported only from Debian 12 (bookworm) and only from the latest point release
• APT sources should be migrated to deb822 .sources files; apt modernize-sources is mentioned as a helper
• For remote upgrades, use screen or tmux and ensure recovery access such as a serial console
• Back up /etc, /var/lib/dpkg, /var/lib/apt/extended_states, and package selections before upgrading
• Install a linux-image-* metapackage after upgrade so future kernel updates are pulled in automatically
• If using encrypted filesystems, ensure systemd-cryptsetup is installed before rebooting
• Plain-mode dm-crypt devices may need explicit cipher, size, and hash settings in /etc/crypttab
• APT sources should point to trixie, trixie-updates, and trixie-security; bookworm entries should be removed after upgrade
• The new default /tmp tmpfs size can be adjusted with systemctl edit tmp.mount or disabled by masking tmp.mount
• apt autoremove is recommended after the upgrade to clean up automatically installed packages
• The old .gpg keyring paths are now compatibility symlinks to .pgp canonical paths and will eventually be removed

• Debian 13 release notes
  https://www.debian.org/releases/trixie/releasenotes
• Debian Installer images and installation guide
  https://www.debian.org/releases/trixie/debian-installer/
• Debian Installer errata
  https://www.debian.org/releases/trixie/debian-installer#errata
• Debian cloud images
  https://cloud.debian.org/

Product Information

Vendor: Debian

Product: Server

Product type: Software

Application category: Utilities

Platform: Linux

Variant: 13 Trixie

Version: Debian 13 (trixie)

Vendor release date: Jul 11, 2026

Original release notes: View on vendor site

Published on updatealert.io: Aug 1, 2026