What are Backports

When Ubuntu releases a new version of its OS every 6 months, that release is largely frozen in time. While the software that is part of that release will get bug fixes and security patches, new major releases of software and the new features that come with them will not be available.

That’s where Ubuntu Backports comes in. Backports offers a way to selectively provide newer versions of software for older Ubuntu releases. Most commonly, the Backports team will provide new versions of standalone applications which can be safely updated without impacting the rest of the system.

Security Support for Backports

Unlike the packages released with Ubuntu, Backports do not come with any security support guarantee. The Ubuntu Security Team does not update packages in Backports. When a package which has been backported receives a security update, the Ubuntu Backporters will make a best-effort attempt to update the backport.

Stability of Backports

When using Backports, it is important to understand that there is an inherent risk in backporting software. Although backported packages are tested by the community before they are included in the repository, there are very occasionally bad interactions with the older software on your system that are overlooked.

Additionally, the very nature of Backports means that backported packages will change the behavior of the package in ways that may be unfamiliar to users of the older versions, and may be incompatible with configuration format and other options of the older versions.

For this reason, the Backports Team recommends configuring the package manager to only install backported packages when they are explicitly requested, which is the default for all Ubuntu releases after and including Ubuntu 11.04 (Natty Narwhal).

Using Backports

There are two steps to configuring Ubuntu Backports; due to changes in Ubuntu, each step may or may not be necessary on a given release.

First, you must ensure that apt is configured with Backports enabled. On releases after and including Ubuntu 11.10 (Oneiric Ocelot), this is not necessary, as apt is configured with Backports enabled by default.

Second, you must determine whether apt should automatically install packages from Backports, or only install packages from Backports when they are manually requested. The Ubuntu Backporters Team recommends the latter option, and this was made the default for all releases after and including Ubuntu 11.04 (Natty Narwhal). The default for releases prior to Ubuntu 11.04 was to automatically install packages from Backports.

Enabling Backports

Backports were not enabled by default for all releases before (but not including) Ubuntu 11.10 (Oneiric Ocelot). On these releases, backports must be manually enabled before you can install packages from Backports.

Enabling Backports on Ubuntu Desktop

1. Open the Software Sources control applet. On Ubuntu 10.10 and earlier, click System -> Administration -> Software Sources. On Ubuntu 11.04 and later, search for Software Sources in the Dash.

2. You will be asked to enter your password. Once you have done that, switch to the Updates tab.

3. Make sure Unsupported updates is checked.

Enabling Backports on Kubuntu

1. Search for and start the Muon Package Manager in the KMenu.

2. Once the Muon Package Manager opens, click Settings -> Configure Software Sources

3. You will be asked to enter your password. Once you have done that, switch to the Updates tab.

4. Make sure Unsupported updates is checked.

Enabling Backports Manually

Make sure the following line is in your /etc/apt/sources.list (substituting your release for trusty):

deb http://archive.ubuntu.com/ubuntu trusty-backports main restricted universe multiverse

For the Ubuntu armhf or arm64 ports use this line instead:

deb http://ports.ubuntu.com/ubuntu-ports trusty-backports main restricted universe multiverse

When Backports Are Installed

Once Backports have been enabled, there are two primary configurations for when the Ubuntu package manager will install packages from Ubuntu Backports. You can configure apt either to always install packages from Ubuntu Backports, or you can configure apt to only install packages from Ubuntu Backports when they are explicitly requested.

On releases before (but not including) Ubuntu 11.04 (Natty Narwhal), apt defaulted to always installing packages from Backports. On later releases, apt only installs packages from Backports when they are explicitly requested.

Because of the potential for unexpected changes when upgrading to a backported package, the Ubuntu Backporters Team recommends configuring apt to only install backported packages on request.

Configuring Backports for Manual Install

Note: This is only necessary on Ubuntu releases before (but not including) Ubuntu 11.04 (Natty Narwhal); releases after and including Ubuntu 11.04 are configured in this mode by default.

1. As root, edit /etc/apt/preferences. You can do this by pressing Alt+F2, typing gksu gedit /etc/apt/preferences in the Dash, and pressing Enter (the file may not already exist, in which case this will create it)

2. Add the following text (substituting your release for trusty):

   Package: *
   Pin: release a=trusty-backports
   Pin-Priority: 100

Configuring Backports for Automatic Install

Note: This is only necessary on releases after and including Ubuntu 11.04 (Natty Narwhal); releases before Ubuntu 11.04 are configured in this mode by default.

1. As root, edit /etc/apt/preferences. You can do this by pressing Alt+F2, typing gksu gedit /etc/apt/preferences in the Dash, and pressing Enter (the file may not already exist, in which case this will create it)

2. Add the following text (substituting your release for trusty):

   Package: *
   Pin: release a=trusty-backports
   Pin-Priority: 500

Installing Backports

If Backports are configured for automatic install, simply install packages as you normally would, using Ubuntu Software Center, Muon, apt-get, or any other tool. The dependencies of the packages being installed will be resolved from Backports.

If Backports are configured for manual install, you have two options.

• Option 1: install the package from Backports, resolve its dependencies from Main.

  To do that append /trusty-backports to the package name. For example:

   apt-get install amarok/trusty-backports

  Option 2: install both the package and its dependencies from Backports.

  To do that specify -t trusty-backports option. For example:

   apt-get install -t trusty-backports amarok

Requesting New Backports

If you would like to request a new backport, please see our documentation on the backport process.

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