Support Pre Upgrade Checks

Providing assurances and useful feedback to deployers preparing to upgrade services vastly improves the upgrade experience. One basic step that we can make consistent across OpenStack projects is to provide “upgrade checks” that can be run prior to upgrade that will help identify any known issues that would result in that upgrade failing.

Each project would provide their specific checks for things like missing or changed configuration options, incompatible object states, or other conditions that could lead to failures upgrading that project. In general, anything that should be documented today in the upgrade release notes would be a good candidate for an upgrade checker to validate.

These checks should perform any upgrade validation that can be automated. There may always be some things that need some subjective evalation, but for those things that can be automated to determine if there is an issue that could impact upgrade success, a validation check should be created to automate it.

Storyboard Board

https://storyboard.openstack.org/#!/board/107

Storyboard Story

https://storyboard.openstack.org/#!/story/2003657

Champion

Matt Riedemann <mriedem.os@gmail.com> has volunteered to drive this goal.

Gerrit Topic

To facilitate tracking, commits related to this goal should use the gerrit topic:

upgrade-checkers

Completion Criteria

In order for a project to call this goal complete it must provide a command in the format:

$PROJECT-status upgrade check

The command must:

  1. Iterate through all defined checks

  2. Provide a summary list output showing:

    • Check name

    • Result (Success or Failure)

    • Details

  3. Return the following codes based on check results:

    • 0 - All checks passed

    • 1 - Warning that one or issues were found that require investigation

    • 2 - One or more checks found an issue that will cause upgrade to fail

  4. Projects with the assert:supports-upgrade tag must integrate their upgrade check command into their upgrade CI testing.

Note

This goal is primarily focused on the traditional stateful service projects like keystone, cinder, glance, etc. However, deployment projects would clearly benefit from integrating these checks into their install and upgrade routines but that is not part of this goal in Stein since some of the service project checks might not even be complete until the end of Stein and thus not consumable to deployment projects until the “T” release at the earliest.

Summary List Output

The $PROJECT-status upgrade check command output should be similar to the following format:

+----------------------------------------------------+
| Upgrade Check Results                              |
+----------------------------------------------------+
| Check: Cells v2                                    |
| Result: Success                                    |
| Details: None                                      |
+----------------------------------------------------+
| Check: Placement API                               |
| Result: Failure                                    |
| Details: There is no placement-api endpoint in the |
|          service catalog.                          |
+----------------------------------------------------+

References

The Nova project has already implemented a nova-status upgrade check command along with several checkers. The command source may be useful as a reference.

The original commit adding the checker framework may also be useful.

The Command Line Reference for the nova-status command provides a good good description with some details on the checks that are performed.

The command line is also used in the grenade upgrade checks for Nova.

Nova contributor reference for nova-status upgrade check: https://review.opendev.org/#/c/596902/

Current State / Anticipated Impact

Most projects today either have their own checklists or tools for checking for upgrade issues, or more commonly, nothing at all. By providing a consistent mechanism to discover known issues we can improve the upgrade process and the deployers confidence and allow for further upgrade tooling to be created.