Ubuntu Wiki

LTS Enablement Stacks

In an effort to support a wider variety of hardware on an existing LTS release, the 12.04.2 and newer point releases will ship with an updated kernel and X stack by default. These newer hardware enablement stacks will be comprised of the newer kernel and X stacks from Quantal, Raring, and S (name TBD). These enablement stacks are only intended for use on x86 hardware at this time. Those running virtual or cloud images should not need this newer enablement stack and are thus recommended to remain on the original Precise stack. To remain on the original Precise stack there are a few options:

• Install from a previous 12.04.0 or 12.04.2 point release and update. The previous 12.04.0 and 12.04.1 releases are archived at http://old-releases.ubuntu.com/

• Update or upgrade to the 12.04 Precise Pangolin from a previous release. Only those installing from the 12.04.2 or newer point release media will automatically receive a newer enablement stack by default.

Below contains additional specifics regarding the exact policies and procedures regarding the support, maintenance, and upgrade paths for these hardware enablement stacks.

12.04.2 + 12.10 Hardware Enablement Stack Policies and Prodecures

1. For the 12.04.2 CD's, we will default to the new Quantal enablement stack. Due to size limitations we are unable to provide options for both the Quantal enablement stack and the original Precise stack.
2. For the 12.04.2 DVD's, we will default to the new Quantal enablement stack as well.
3. The 12.04.0 and 12.04.1 point releases will be archived and available at old-releases.ubuntu.com.
4. For the 12.04.2 CD's and DVD's, we will message that anyone installing and wishing to remain on the original 12.04 stack to please install from the 12.04.0 or 12.04.1 media and update.

   1. For the 12.04.2 point release, https://help.ubuntu.com/ and http://www.ubuntu.com/download/desktop should be updated to message/notify users that they do have the option to install with the 12.04.1 media as an alternative to remain on the original Precise stack. A link to the 12.04.1 media which will be archived at old-releases.ubuntu.com should also be referenced in this message.

5. We only intend to support enablement stack package combinations in 12.04 which are derived from the same release, eg. the 12.10 X.org must be used in conjunction with the 12.10 kernel and vice versa. Intermixing a 12.10 enablement kernel with the 12.04 X.org stack or a 12.10 enablement X.org stack with a 12.04 kernel will not be officially tested nor supported.
6. Anyone running with the original Precise stack will not be automatically updated to the new Quantal enablement stack. Users can electively choose to install the Quantal (or newer) enablement stack meta package if they wish to do so.
7. Additionally, anyone upgrading to Precise will not be automatically upgraded to the new Quantal enablement stack. Again, they can electively choose to do so by manually installing the appropriate meta package.
8. The original 12.04 stack in Precise will remain supported for the usual 5yr life cycle of the LTS release.
9. Anyone running with the newer Quantal enablement stack will remain on that stack until the following 14.04 LTS enablement stack is available and supported in 12.04. Users will *not* be automatically rolled forward to interim non-LTS enablement stack offerings.
   1. If anyone is interested in updating to newer enablement stack offerings in Precise as they become available, we will provide series specific meta packages which they can manually choose to install. We will also provide a rolling release meta package for those who do want to roll forward automatically. Again, this will be an elective package install and not mandatory.
10. When an interim non-LTS enablement stack offering (ie Q|R|S enablement stack in P) reaches it's EOL, users will be automatically rolled forward to the 14.04 LTS enablement stack, eg 12.10 enablement stack users will be automatically upgraded to the 14.04 enablement stack in Precise upon the 12.10 enablement stack reaching it's EOL. This will ensure a continuous line of support. See item 11 below for follow on discussions.
11. The interim non-LTS enablement stacks (ie Q|R|S enablement stacks in P) will only be supported in Precise from the time they appear in a point release through the remainder of their natural release life cycle
    1. The one caveat here is the 12.10 enablement stack will be supported slightly longer until the first 14.04 SRU for the kernel and X.
    2. Background: There are concerns that 12.10 will EOL at the same time 14.04 is released. Some are in favor of driving a more rigorous QA effort of the 14.04 enablement stack in 12.04 to ensure an immediate and smooth transition to the 14.04 enablement stack on the day the 12.10 enablement stack EOL's. This would also likely result in an increased level of quality for the initial 14.04 release due to the extra testing focus. Others are however more conservative and would prefer we not offer the 14.04 enablement stack in Precise until the 14.04.1 time frame. We commonly message that users should not be using an LTS release for production environments until the .1 release. It seems reasonable that we should message the same advice for the enablement stacks and subsequently not automatically upgrade users of the 12.10 enablement stack until the 14.04.1 time frame. This provides an additional 3mo window where we would benefit from bug fixes and overall testing we receive in the initial months following 14.04's release. However, the disadvantage here is this extends the support window of the 12.10 enablement stack in Precise beyond it's natural support window in it's original 12.10 release. It produces a larger maintenance burden as well as a slightly more complicated policy which would need to be messaged. As a compromise between the two, we've decided to support 12.10 up until the first SRU for the kernel/X in 14.04.
12. Anyone running an R or S enablement stack in Precise might have an unexpected result if they upgrade their entire system to Quantal. The packages offered in the R/S enablement stack would supersede the Quantal packages. Decision was for update-manager to only prompt to upgrade to the next LTS release, which is how it is already. Otherwise, there should be some type of package conflicts/replace in place to prevent this from happening. This is only a real concern for the R and S stacks.
13. Apport has and will be updated to allow bug reporting in Precise against the enablement stacks. These bugs will also be appropriately tagged to assist in searching.
14. Only the -generic kernel flavor from Quantal will be supported in Precise.