Web / Traefik Interview questions
How can you optimize Traefik for high-availability deployments?
Traefik itself is stateless with respect to routing decisions, so horizontal scaling starts with running multiple replicas behind a Layer 4 load balancer (or as a Kubernetes Deployment with multiple pods), each independently watching the same providers and converging on the same dynamic configuration.
The one piece of state that does need coordination is ACME certificate storage: if every replica manages its own acme.json independently, they can race each other requesting the same certificate and hit Let's Encrypt rate limits, so production HA setups typically use a shared KV store (like Consul or etcd) or run a dedicated leader-elected instance for certificate resolution.
Health checks and readiness probes on Traefik's own entrypoints matter too, so the front-end load balancer only sends traffic to replicas that have finished loading their initial dynamic configuration, avoiding a window where a freshly started pod returns 404s for routes it hasn't discovered yet.
Finally, keeping the provider watch connections lightweight (scoping Kubernetes RBAC and watched namespaces tightly, for instance) reduces the blast radius and resource cost of running several replicas against the same cluster API.
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