Some drivers included in the Linux kernel used to contain non-free firmware blobs. Starting from squeeze this firmware has been moved to separate packages in the non-free section of the archive, such as firmware-linux. If such packages are installed, the firmware will be loaded automatically when required.

The preferred program for interactive package management from a terminal is aptitude. For a non-interactive command line interface for package management, it is recommended to use apt-get. apt-get is also the preferred tool for upgrades between major releases. If you are still using dselect, you should switch to aptitude as the official front-end for package management.

For squeeze APT automatically installs recommended packages by default^[2]. This can be changed by adding the following line in /etc/apt/apt.conf:

APT::Install-Recommends "false";

An important improvement in the Debian GNU/Linux boot system is the introduction of dependency-based boot sequencing and parallel boot. This feature is enabled by default in new installs and it will be enabled for upgrades from lenny, if possible.

This feature is enabled through the use of insserv by sysv-rc to order init.d scripts based on their declared dependencies^[3]. It has been possible after a sustained effort to adapt all the boot scripts of packages provided in the distribution as well as the boot system itself.

With dependency-based boot sequencing it is also now possible to run the boot system scripts in parallel which can, under most circumstances, improve the speed of the boot process. This feature is enabled by default, in new systems and upgrades, whenever possible. To disable it specify

CONCURRENCY=none

in /etc/default/rcS. For more information on this feature refer to the information available in /usr/share/doc/insserv/README.Debian.

In this new release, the settings for the keyboard have been unified so that both the console and the Xorg server use the same settings. The keyboard settings are now defined in the /etc/default/keyboard configuration file which overrides the keyboard defined in Xorg's configuration file.

The console-setup package now handles the keyboard for both environments as well as the font configuration for the console. You can reconfigure the keyboard layout and related settings by executing dpkg-reconfigure keyboard-configuration or by manually editing the /etc/default/keyboard configuration file.

Graphics mode setting code for the most common desktop chipsets (from Intel, ATI/AMD and NVIDIA) has moved from the respective Xorg drivers to the Linux kernel. This provides a number of advantages, such as:

More details are in 節 5.6, “Graphics stack changes” and in the Debian wiki.

This Debian release comes with several options for implementing client-side authentication using LDAP. Users of the libnss-ldap and libpam-ldap packages should consider upgrading to libnss-ldapd and libpam-ldapd.

These newer packages delegate the LDAP queries to a central unprivileged daemon (nslcd) that provides separation between the process using the LDAP information and the daemon performing LDAP queries. This simplifies handling of secured LDAP connections, LDAP authentication credentials, provides a simpler mechanism to perform connection fail-over and debugging and avoids loading LDAP and related libraries into most applications.

Upgrading to libnss-ldapd and libpam-ldapd should be easy as existing configuration information will be mostly reused. Only for advanced configuration should any manual reconfiguration be necessary.

These packages however currently lack support for nested groups and only support password change using the LDAP password modify EXOP operation.

All changes to the released stable distribution (and to oldstable) go through an extended testing period before they are accepted into the archives. Each such update of the stable (or oldstable) release is called a point release. Preparation of point releases is done through the proposed-updates mechanism.

Packages can enter proposed-updates in two ways. Firstly, security-patched packages added to security.debian.org are automatically added to proposed-updates as well. Secondly, Debian GNU/Linux developers may upload new packages to proposed-updates, where they get added after review by the Stable Release Managers. The current list of packages can be seen at http://ftp-master.debian.org/proposed-updates.html.

如果在這些套件正式加入小改版之前您想要幫忙測試這些更新的話，您可以將 proposed-updates 區段加入您的 sources.list裡：

deb     http://mirrors.kernel.org/debian squeeze-proposed-updates main contrib
deb-src http://mirrors.kernel.org/debian squeeze-proposed-updates main contrib

The next time you run apt-get update, the system will become aware of the packages in the proposed-updates section and will consider them when looking for packages to upgrade.

這嚴格來說並不是 Debian 的新功能，只是之前不太為人所知罷了。

Some packages from proposed-updates may also be made available via the squeeze-updates mechanism. This path will be used for updates which many users may wish to install on their systems before the next point release is made, such as updates to virus scanners and timezone data. All packages from squeeze-updates will be included in point releases.

Note that this replaces the functionality previously provided by the volatile.debian.org archive.

In order to use packages from squeeze-updates, you can add an entry to your sources.list:

deb     http://mirrors.kernel.org/debian squeeze-updates main contrib
deb-src http://mirrors.kernel.org/debian squeeze-updates main contrib

The next time you run apt-get update, the system will become aware of the packages in the squeeze-updates section and will consider them when looking for packages to upgrade.

When a new package is made available via squeeze-updates, this will be announced on the debian-stable-announce mailing list.

The service provided by the backports.org repositories has been integrated in Debian infrastructure and is now an official Debian service, hosted at backports.debian.org.