Learning About Debian LTS

This page briefly describes what Debian LTS is, primarily from a user perspective, answering some common questions, and providing links to other documents with more detailed information. After reading this page you should have a relatively complete understanding

What is Debian LTS?

Debian LTS, or more verbosely Debian Long Term Support, is an effort initiated by Freexian SARL to ensure that each Debian stable release receives full security support for 5 years following the date of initial release.

Debian LTS is not a separate release (for example, the way that some Linux distributions designate certain releases as LTS and others as non-LTS), but rather is a component of the lifecycle of every Debian release. In that way, Debian LTS is not really separate from a particular Debian release. Information about Debian release lifecycles as they relate to LTS can be found in the Debian Wiki.

However, there are still some differences since the Debian LTS Team is a separate and distinct entity from the Debian Security Team, though both teams work in close collaboration. This page and those which follow explain where these differences are important to users.

What is the history of Debian LTS?

Historically, Debian releases received support from the Debian Security Team from the date of release until 1 year after the next stable release. In general, this was about 3 years in total. The efforts of the Debian LTS Team began in 2014, under the leadership of Freexian, in order to extended this to 5 years in total for each Debian release, as detailed here.

What is included as supported in LTS?

The Debian LTS Team does its best to provide a level of support comparable to what the Debian Security Team provides during the first 3 years after a stable release. Though, in practice the Debian LTS Team is not able to cover everything in exactly the same way.

Full support extends for 5 years to:

  • All packages in the Debian archive in the main, contrib, non-free, and non-free-firmware sections (except for the reduced support accorded those with limited support)

  • The most popular hardware architectures (currently amd64, i386, arm64, armel, and armhf)

Additionally, Freexian is working diligently with other vendors and upstream developers of key packages to provide a more robust level of support.

How is LTS different from “regular” security support?

While the goal is to provide a user experience that is as seamless as possible, because there are two different teams at work (the Debian Security Team up to 3 years from the initial release and the Debian LTS from 3 years up to 5 years) there are some differences.

If you are a normal user (whether using a single personal system or managing a fleet of thousands of servers), then “regular” security support and LTS are not meaningfully different in most cases. You can simply use your Debian system or systems up until 5 years from the date of release and rely on normal security updates through the entire 5 year period. Though, you should be aware of a few important differences which may affect you depending on your circumstances.

When a particular Debian release is made, any limitations in security support are described in the release notes and those limitations continue to apply during the LTS phase of the lifecycle. Additionally, when a Debian release enters the LTS phase of the lifecycle, the following additional limitations apply:

  • a reduced range of hardware architectures are supported

  • announcements concerning security updates are published differently

  • backports are not supported after 3 years from the initial release date (the team which supports backports is separate from the Debian Security Team and their commitment stands at 3 years)

  • packages which have passed the point of being supportable may be dropped from support, or they may be updated to entirely new versions

  • no further point releases, no new installers, and no new installer image releases after 3 years from the initial release date (the teams which support these activities are separate from the Debian Security Team and their commitment stands at 3 years)

Additional information concerning these limitations and how to deal with them can be found at Getting Started With Debian LTS.

What if 5 years is insufficient (for me)?

Depending on your particular circumstances and use cases, 5 years of support may not be sufficient. If that describes your situation, then you may benefit from a supplemental subscription offering from Freexian, Extended LTS. This offering provides limited scope support for a specific subset of packages based on your particular system configuration until 10 years from initial release. Additional information concerning Extended LTS is available in the Debian Wiki.

What’s next?

If you would like to start using LTS, then see Getting Started With Debian LTS.

If you are already using LTS and would like to know how to get help with it, then see Getting Help With Debian LTS.

To become a sponsor of LTS, please have a look at Sponsoring Debian LTS.

If you are a developer and have an interest in contributing to LTS in a technical capacity, then see Contributing to Debian LTS.