2024-09-06: Enable new allowed_plans mechanism for instance runners on GitLab.com

Production Change

Change Summary

We've recently merged and deployed a new mechanism for handling allowed_plans feature. Now we need to configure it properly and switch the feature flags for it.

Details of the feature flags rollout are described at [Feature flag] Finalize ci_runner_separation_by... (gitlab-org/gitlab#432167 - closed) • Tomasz Maczukin • 18.2. Details of the new configuration are described at https://gitlab.com/gitlab-org/ci-cd/shared-runners/infrastructure/-/issues/242+s

Change Details

1. Services Impacted - ServiceCI Runners
2. Change Technician - @tmaczukin
3. Change Reviewer - @rehab
4. Time tracking - 1h
5. Downtime Component - none

Set Maintenance Mode in GitLab

If your change involves scheduled maintenance, add a step to set and unset maintenance mode per our runbooks. This will make sure SLA calculations adjust for the maintenance period.

Detailed steps for the change

Change Steps - steps to take to execute the change

Estimated Time to Complete (mins) - 20m

• Set label changein-progress /label ~change::in-progress
• Execute this script in the GPRD rails console
• Enable needed feature flags:
  • /chatops run feature set ci_queuing_include_allowed_plans true
  • /chatops run feature set ci_runner_separation_by_plan true
• Notify the #support_gitlab-com and #g_hosted_runners Slack channels
• Set label changecomplete /label ~change::complete

Rollback

Rollback steps - steps to be taken in the event of a need to rollback this change

Estimated Time to Complete (mins) - 5m

• Disable related feature flags:
  • /chatops run feature set ci_queuing_include_allowed_plans false
  • /chatops run feature set ci_runner_separation_by_plan false
• Set label changeaborted /label ~change::aborted

Monitoring

Key metrics to observe

• Metric:

  • Location: https://dashboards.gitlab.net/goto/oIKPw1qIR?orgId=1

  • What changes to this metric should prompt a rollback:

    Any significant drop down of the metric line should be considered a sign of things going not as expected.

Change Reviewer checklist

C4 C3 C2 C1:

• Check if the following applies:
  • The scheduled day and time of execution of the change is appropriate.
  • The change plan is technically accurate.
  • The change plan includes estimated timing values based on previous testing.
  • The change plan includes a viable rollback plan.
  • The specified metrics/monitoring dashboards provide sufficient visibility for the change.

C2 C1:

• Check if the following applies:
  • The complexity of the plan is appropriate for the corresponding risk of the change. (i.e. the plan contains clear details).
  • The change plan includes success measures for all steps/milestones during the execution.
  • The change adequately minimizes risk within the environment/service.
  • The performance implications of executing the change are well-understood and documented.
  • The specified metrics/monitoring dashboards provide sufficient visibility for the change.
    • If not, is it possible (or necessary) to make changes to observability platforms for added visibility?
  • The change has a primary and secondary SRE with knowledge of the details available during the change window.
  • The change window has been agreed with Release Managers in advance of the change. If the change is planned for APAC hours, this issue has an agreed pre-change approval.
  • The labels blocks deployments and/or blocks feature-flags are applied as necessary.

Change Technician checklist

• Check if all items below are complete:
  • The change plan is technically accurate.
  • This Change Issue is linked to the appropriate Issue and/or Epic
  • Change has been tested in staging and results noted in a comment on this issue.
  • A dry-run has been conducted and results noted in a comment on this issue.
  • The change execution window respects the Production Change Lock periods.
  • For C1 and C2 change issues, the change event is added to the GitLab Production calendar.
  • For C1 and C2 change issues, the SRE on-call has been informed prior to change being rolled out. (In #production channel, mention @sre-oncall and this issue and await their acknowledgement.)
  • For C1 and C2 change issues, the SRE on-call provided approval with the eoc_approved label on the issue.
  • For C1 and C2 change issues, the Infrastructure Manager provided approval with the manager_approved label on the issue.
  • Release managers have been informed prior to any C1, C2, or blocks deployments change being rolled out. (In #production channel, mention @release-managers and this issue and await their acknowledgment.)
  • There are currently no active incidents that are severity1 or severity2
  • If the change involves doing maintenance on a database host, an appropriate silence targeting the host(s) should be added for the duration of the change.