Ubuntu Wiki

Overview

This page documents the Stable Release Update process for the Ubuntu Cloud Archive.

Stable Release Updates

The SRU process for the Ubuntu Cloud Archive follows the same process as the Ubuntu Stable Release Update process.

The following bullets highlight some key points that are mostly covered in detail in the Ubuntu SRU process (for more details see the link above):

• Users of official releases expect a high degree of stability.
• It is critically important to treat SRUs with great caution.
• SRUs must be accompanied by a strong rationale and present a low risk of regression.
• Minimizing risk tends to be well-correlated with minimizing the size of the change. As such, the same bug may need to be fixed in different ways in stable and development releases.
• Stable release updates will, in general, only be issued in order to fix:

  • New upstream stable point releases for OpenStack core packages which group several bug fixes

  • High-impact bugs (e.g. security vulnerabilities, severe regressions, loss of user data)
  • Bugs that are not high-impact, but have an obviously safe patch

• SRUs must have an accompanying bug with well-documented sections for [Impact], [Test Case], and [Regression Potential]. These sections must contain details as described in the Ubuntu Stable Release Update process.

• Bugs must first be fixed in the latest upstream release where the bug exists, if possible [1]. At this point the fix can be backported to the corresponding Ubuntu release [2]. Once the bug has been fixed in the corresponding Ubuntu release, it can then be backported to the corresponding UCA. The same bug may then be fixed in the prior upstream release, followed by being backported to the corresponding Ubuntu release, followed by being backported to the corresponding UCA. And then it can be fixed in Liberty, Kilo, etc.

  • [1] Landing a fix upstream may not be possible once the upstream branch is in critical-fix or security-fix only mode, or once it has reached EOL. See the OpenStack upstream stable branch policy, which specifies the various phases of support for stable branches, which are typically supported for 12 to 18 months. This case must be handled with extreme caution, as fixes would be released directly to the corresponding Ubuntu release without having landed upstream first.

  • [2] Landing a fix in a corresponding Ubuntu release may not be possible once the Ubuntu release has reached EOL. This case must also be handled with extreme caution, as fixes would be released directly to the corresponding UCA without having first landed in the corresponding Ubuntu release, and possibly without having first landed in the upstream OpenStack release.

Getting Package Source

Depending on the package and the release, there are different ways to download the package source:

• Core OpenStack packages for Liberty+ are maintained in git on Launchpad. The process for working with these repositories is documented here.

• Core OpenStack packages prior to Liberty can be found maintained in Bazaar on Launchpad. The process for working with these branches is documented here.

• UCA packages that correspond to a supported Ubuntu release can be retrieved with the pull-lp-source tool.

  • pull-lp-source <package> [release|version] (e.g. pull-lp-source python-oslo.messaging xenial)

• UCA packages that correspond to an unsupported Ubuntu release can be retrieved from the corresponding UCA staging PPA.

  • If the corresponding Ubuntu release has reached end of life, then the package source can be retrieved directly from the UCA staging PPA. For example, see the Mitaka staging PPA.

Providing A Fix

Fixes can be provided as:

• A debdiff attached to the SRU bug
• Package source pushed to a git repo (or bzr branch).