DebianReleases > OldStable
oldstable is a codename for the previous Debian stable repository, as long as security updates are provided. It is not just a name of the old stable version(s) of Debian.
When security updates are not provided anymore for oldstable, the repository is moved to http://archive.debian.org/.
Buster is the current oldstable.
- Q) Why oldstable ?
- A.1) In a large organisation, it can take a while to plan, test and upgrade all computers.
- A.2) Some Debian based custom distribution's stable version can be based on oldstable. Having oldstable is convenient for them too.
- Q) When is it released ?
The old-stable is "created" 1 just before a new stable is released.
- Q) How long will security updates be provided?
The security team tries to support a stable distribution for about one year after the next stable distribution has been released, except when another stable distribution is released within this year. It is not possible to support three distributions; supporting two simultaneously is already difficult enough. source: Debian Security FAQ
Status/Stable - Current status of Stable
DebianReleases - more about the different Debian releases.
LTS The Long Term Support project provides limited support for some releases after they are not oldstable any more.
It's just a symlink to the distribution codename (1)