2021-10-27: The transactions_replica SLI of the patroni-registry service (`main` stage) has an error rate violating SLO
Current Status
Fixing permissions for postgres_exporter on the (not yet enabled) registry-db enabled it to report transaction rollback metrics. This started to trigger alerts because gitlab-monitor
is doing some failing DB requests (since the beginning) because of missing permissions. There is no customer impact, as the DB isn't taking production traffic yet.
Timeline
Recent Events (available internally only):
- Deployments
- Feature Flag Changes
- Infrastructure Configurations
- GCP Events (e.g. host failure)
All times UTC.
2021-10-27
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13:40
- @hphilipps fixing postgres_exporter permissions, causing it to start reporting tx rollbacks for gitlab-monitor -
14:11
- @igorwwwwwwwwwwwwwwwwwwww declares incident in Slack. -
15:18
- stopping gitlab-monitor makes tx rollback count stop, confirming that gitlab-monitor was the culprit -
15:27
- alert silenced for 2h until gitlab-monitor permissions get fixed -
16:00
- granting necessary permissions to gitlab-monitor resolves the alert
Corrective Actions
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Incident Review
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Customer Impact
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Incident Response Analysis
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Post Incident Analysis
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Lessons Learned
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