PREQUEL-2025-0098
Loki Pattern Ingester Empty RingMediumImpact: 6/10Mitigation: 4/10
Description
Loki distributor encounters "empty ring" errors when attempting to send streams to pattern ingesters.\nThis occurs when pattern ingestion is enabled in the configuration but no pattern-ingester pods are \nrunning or properly registered in the ring. The distributor's pattern-tee component cannot find any\navailable pattern ingesters to process pattern extraction, leading to high error spam in logs while\nnormal log ingestion continues to function.\n
Mitigation
- Verify pattern-ingester pods are deployed with replicas › 0 in Helm values\n- Check pattern-ingester pod status: kubectl get pods -l app.kubernetes.io/component=pattern-ingester -A\n- Ensure pattern_ingester.enabled: true AND patternIngester.replicas: 1+ in Helm configuration\n- Verify ring membership: curl http://localhost:3100/ring from distributor pod\n- Check pattern-ingester logs for startup or ring join errors\n- Validate KV store and gossip configuration consistency across components\n- Confirm network policies allow distributor to pattern-ingester communication\n- Verify pattern-ingester replication factor is set to 1\n- Review pattern-ingester port configuration and health check endpoints\n