Through one address Steward read whichever replica answered, and with host-mode ports behind a keepalived VIP that can be the replica serving nothing: since the 18:43 restart every scrape landed on Docker03's idle Traefik, which has no traefik_service_* series, so no router was stored. A metrics_url host name that resolves to several addresses (a swarm service's tasks.<service>, a Kubernetes headless Service, round-robin DNS) is now scraped address by address, with the original Host header and TLS name. Answers from one process are kept once; a replica that doesn't answer is skipped with a warning. Requests, bytes and latency buckets are summed over the replicas that have a baseline, so the sum's rise is the sum of each one's own rise; certificates are listed once; Traefik's own figures add connections and memory and keep the newest reload. A name with one address is one scrape, as before. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>