walinuxagent Updates

This document describes the process to update and test new versions of the walinuxagent package in SRUs.

The walinuxagent package is an Ubuntu distribution of the upstream Microsoft Azure Linux Agent that manages Linux provisioning, and VM interaction with the Azure Fabric Controller. For a detailed list of functionality this package provides to Ubuntu cloud images, refer to the upstream project page at GitHub: https://github.com/Azure/WALinuxAgent

Cloud platforms evolve at a rate that can't be handled in six-month increments, and they will often develop features that they would like to be available to customers who don't want to upgrade from earlier Ubuntu releases. As such, updating walinuxagent to more recent upstream releases is required within all Ubuntu releases, so they continue to function properly in their environment.

New versions of walinuxagent can be SRU'd in to older releases provided the following process is followed.

QA Process

When a new version of walinuxagent is uploaded to -proposed, the following will be done:

• the CPC team will write new automated tests to cover new testable functionality (if any) in the new package
• the automated testing that the CPC team normally runs against Azure images before they are published will be run against the -proposed package
• the Microsoft Azure Linux Agent team will be asked to validate
  • that the new package addresses the issues it is expected to address, and
  • that the new package passes their internal image validation, with emphasis on walinuxagent extension support.

In addition, prior to being uploaded to -proposed, the CPC team does the following testing

• The new package candidate version is built in a PPA and tested on the target suite before being uploaded to the archive at all. This will involve one or both of:
  • Installing the PPA packages on an Azure VM, manually restoring the VM to a first boot state and rebooting it,
  • Generating a fresh image with the PPA package version preinstalled and testing that directly
• Once the manual packaging tests pass successfully and the package requires no further changes, it will be uploaded to the archive.
• Once accepted in to -proposed, a test image is built from -proposed, which is subjected to the full CPC image tests; this tests for more regressions across multiple Azure instance sizes. This includes tests for the following bugs:

  • Bug #1479610 regression on dhcp configuration

  • Bug #1079897 mangled server identity and access on upgrade

  • Bug #1305418 breaks sshd configuration

Pre-SRU Test Cases

These are the test cases that all walinuxagent are subjected to before even getting to SRU:

[Test case 1]: Upgrade testing
1.) Launch instance on Azure
2.) Upgrade walinuxagent (usually from PPA)
3.) Confirm that "waagent" is running, check /var/log/waagent.log for errors
4.) Reboot, repeat step 3
5.) Remove /var/lib/cloud and /var/lib/waagent (to simulate first boot conditions)
6.) Reboot, repeat step 3
7.) Repeat step 5, capture the instance as an image and provision a new instance from it; repeat step 3
  
[Test Case 2]: New instance
1.) Build new cloud image with PPA package
2.) Boot instance
3.) Confirm that instance provisioned

SRU Test Cases

These are automated tests:

1.) Build new cloud image with -proposed package
2.) Boot instance
3.) Confirm that instance provisioned
4.) Run standard tests and regression tests
5.) Repeat from step 2 for all other Azure VM Sizes.

SRU Template

== Begin SRU Template ==
[Impact]
This release contains both bug-fixes and new features and we would like to
make sure all of our supported customers have access to these improvements.
The notable ones are:

   * <TODO: list any LP: # included>

See the changelog entry below for a full list of changes and bugs.

[Test Case]
The following development and SRU process was followed:
https://wiki.ubuntu.com/walinuxagentUpdates

The Microsoft Azure Linux Agent team will execute their testsuite, which
includes extension testing , against the walinuxagent that is in
-proposed.  A successful run will be required before the proposed walinuxagent
can be let into -updates.

The CPC team will be in charge of attaching a summary of testing to the bug.  CPC team members will not
mark ‘verification-done’ until this has happened.

== End SRU Template ==

<TODO: Paste in change log entry>