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Runbook: Investigate a Loki Query Failure
1 · Prerequisites
Confirm every item is in place before any state change.
- Loki
- A user reporting the failure
2 · Pre-checks
Read-only diagnostic commands. If any of these don't match expected output, stop and investigate further.
- · Determine the query
- · Determine when it last worked
3 · Procedure
Execute each step in order. Verify the expected output of a step before moving to the next.
- 1Test the query in Grafana Explore
- 2If syntax error: revise the query
- 3If range too wide: narrow it
- 4If stream selector wrong: verify labels
- 5If regex expensive: simplify
- 6Check distributor and querier metrics
4 · Verification
Confirm the procedure actually fixed the problem.
- ✓The query returns expected logs
- ✓loki_query_duration_seconds shows reasonable latency
5 · Rollback
If verification fails, undo the procedure in reverse order.
- ↶N/A (correction only)
6 · Escalation
When the runbook isn't enough, contact:
- · N/A
Purpose
Investigate a Loki Query Failure
When to use this runbook
Use this runbook when the operator needs a guided procedure to handle the situation described above.
Pre-checks
Before starting the procedure, confirm the prerequisites and pre-checks are met. The structured lists are rendered from the frontmatter by the page layout.
Procedure
Follow the steps from the frontmatter procedure steps. The page layout renders the steps as a checklist with copy-to-clipboard affordances.
Verification
After the procedure, the structured verification items from the frontmatter are rendered as a checklist.
Rollback
If the procedure fails or makes things worse, follow the structured rollback steps from the frontmatter.
Escalation
The structured escalation path is rendered from the frontmatter. Use it if the operator cannot complete the procedure safely.