Monitoring Stack Field Notes

Logs and traces are most useful when they connect to the same incident question as the alert. Loki and Tempo can provide that path, but only if labels, trace IDs, retention, and dashboard links are designed before the outage. Start From The Alert An alert should lead to a dashboard, and the dashboard should lead to logs and traces for the same scope. The path should be obvious: alert -> service dashboard -> Loki logs by service/namespace -> Tempo traces by trace ID or exemplar If responders must invent the LogQL query during every incident, the observability stack is not finished. ...

Prometheus is easy to start and easy to overload. Most production problems are not caused by one bad alert. They come from unclear scrape ownership, high-cardinality labels, expensive dashboard queries, or rule changes that nobody can explain during an incident. The same ownership rule applies to observability agents. If Grafana Alloy collects logs, give it resource limits and backend-readiness checks too. See Grafana Alloy Log Collector CPU Guardrails. Own The Scrape Path Every scrape target should have an owner and a reason to exist. ...

Long-term metrics systems solve one problem and create several new ones. Thanos and Mimir can extend Prometheus retention, centralize query, support multi-cluster visibility, and make historical analysis possible. They also introduce object storage, compaction, tenancy, query limits, and failure modes that are easy to miss when the first dashboard loads. Define The Retention Contract Decide retention by use case: recent incident response. capacity planning. SLO reporting. audit or compliance review. seasonal comparison. cost allocation. Do not keep everything forever by default. Long retention with uncontrolled cardinality becomes a storage and query reliability problem. ...