DNS for Engineers
How TTLs really affect changes, why propagation feels slow, where DNS failover helps and where it doesn’t, plus cutover playbooks that keep rollback easy.
Tiny explainers grouped by topic. Spend less time Googling, more time building.
How TTLs really affect changes, why propagation feels slow, where DNS failover helps and where it doesn’t, plus cutover playbooks that keep rollback easy.
Three edge layers, three different jobs: one shapes HTTP traffic, one spreads load, one enforces API policy. Here’s where each belongs.
Design request deadlines, hop timeouts, and idempotent retries with jitter so you protect upstreams, tame tail latency, and avoid cascading failures.
DNS changes feel slow because of caching everywhere: resolvers, browsers, OSes, CDNs, and parent zones. Here’s the mental model, typical timelines, and how to plan zero‑drama cutovers.
From DNS lookup to TLS to paint: the shortest useful tour of what the browser actually does after you hit Enter.