CR [GSTG] Add dedicated WAL disk to patroni-registry cluster (disk will not be used jet)
Production Change
Change Summary
This CR will add a dedicated WAL disk to each node of the patroni-registry
cluster in [GSTG].
The disks will be created, but not yet used.
This is the first step to investigate into the behavior and to create the needed roles.
Change Details
- Services Impacted - ServicePatroniRegistry
- Change Technician - @alexander-sosna
- Change Reviewer - DRI for the review of this change
- Time tracking - < 60 minutes
- Downtime Component - No downtime
Detailed steps for the change
Change Steps - steps to take to execute the change
Estimated Time to Complete (mins) - 30
-
Set label changein-progress /label ~change::in-progress
-
Merge Adds dedicated WAL disk to [GSTG] patroni registry, to add the additional disks to the cluster nodes. -
Wait for the pipelines to run and apply the change, gl-infra/config-mgmt/-/pipelines -
Check if the new disks are available with sudo df -h
, if not executetf apply
manually -
Observe metrics for 10 minutes -
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) - 30
For the disk are just added, not used the impact of having the disks attached should be minimal. Need of rollback is unlikely.
-
Revert Adds dedicated WAL disk to [GSTG] patroni registry, to remove the additional disks to the cluster nodes. -
Wait for the pipelines to run and apply the change, gl-infra/config-mgmt/-/pipelines -
Check if the new disks are removed with sudo df -h
, if not executetf apply
manually -
Set label changeaborted /label ~change::aborted
Monitoring
Key metrics to observe
- Metric:
patroni-registry Service Error Ratio
/patroni-registry Service RPS - Requests per Second
- Location: https://dashboards.gitlab.net/d/patroni-registry-main/patroni-registry3a-overview?orgId=1&var-PROMETHEUS_DS=PA258B30F88C30650&var-environment=gstg
- What changes to this metric should prompt a rollback: If metrics indicate not functioning cluster, investigate. Rollback might not help.
Change Reviewer checklist
-
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.
-
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.
Edited by Biren Shah