One of the primary confusion points we have right now is with the definitions of the following, and what they mean:
- End of Standard Support (EoSS)
- Long Term Support (LTS)
- Extended Security Maintenance (ESM)
- End of Life (EoL)
A while ago, the Community Council raised this with Canonical and we got a definitions page written up on the Wiki (managed by Canonical) for this. This wiki tries to explain to the end user in the least technical ways what the various support periods are, and are the basis of the rules regarding EoSS, ESM, and EoL equivalent 'support' meanings here on Ask Ubuntu: https://wiki.ubuntu.com/supportperiod
A similar question was brought up regarding "Long Term Support" releases because flavor releases have a 3 year LTS period instead of a 5 year period - this is explained in greater detail here: How long do we support Ubuntu flavors?
To summarize all the above data though, and put it into the Ask Ubuntu mindset:
Standard Support, and End of Standard Support (EoSS)
All Ubuntu releases have a support period of 'standard support'. This is the time in which a given release is considered 'supported' by the community.
This is usually a period of 9 months from a given release date for a given version of Ubuntu, except for Long Term Support (LTS) releases which have 5 years of support for the release.
At the end of the term of Standard Support for a given release, Ask Ubuntu will no longer consider new posts for that release on topic on Ask Ubuntu.
For non-LTS releases, the end of Standard Support is also the End of Life (EoL) of the release.
Long Term Support
Long Term Support refers to releases of Ubuntu that have longer terms of Standard Support (as stated above, this is a 5 year support period for a given release of Ubuntu or its flavors).
LTS releases of Ubuntu are supported on Ask Ubuntu throughout the 5 year lifecycle of the release. At the end of the 5 years of Standard Support, an LTS release migrates into what is called Extended Security Maintenance, which is a Canonical offering.
At the end of the Standard Support period of 5 years, LTS releases are considered offtopic here on Ask Ubuntu.
Extended Security Maintenance (ESM)
Extended Security Maintenance is a period after an LTS's given release where you must register for Ubuntu Advantage for Infrastructure - Essential level. This is 'free' for a limited number of systems for personal users, and is not free for corporate users.
During the ESM period, a release that is enrolled in ESM will receive security patches for packages that are part of the base Ubuntu operating system in the Main pocket of the Ubuntu repositories.
Releases of Ubuntu in the ESM period are NOT on topic here on Ask Ubuntu, as this is considered beyond the end of standard support.
End of Life (EoL)
An End of Life release is:
- Any non-LTS release which has reached the end of its standard support period (EoSS), or
- Any LTS release which has gone past both its standard support period (and is thus EoSS) and which has also gone past the 5 year period that ESM was available for that release.
End of Life releases are considered dead and no longer supported by the Ubuntu community as a whole. As such, End of Life releases are considered offtopic on Ask Ubuntu.