Sakewa mara saituwa yana nufin fitar da sabon sifofin sanarwa ba tare da bugatarwa ta yaya ga mai amfani — aikace-aikacen ya kasance akwai kudu jiya. Samun shi yana buƙatar hanyoyin sanarwa masu tunani, canja masu juna daidai, dukan lafiya, da sakin tsiratarwa masu kirki na bukattun bakin jiya.
Abin da sakewa mara saituwa ke buƙatarwa
GOAL: deploy a new version with NO user-facing downtime (always-available service):
→ never take the whole service offline to deploy
→ always have healthy instances serving while updating others
→ handle in-flight requests gracefully (don't drop them mid-request)
→ Combine several techniques (below).
Mahimmancin hanyoyi
✓ DEPLOYMENT STRATEGY — rolling, blue-green, or canary (never all-at-once downtime):
→ rolling: update instances gradually (others keep serving)
→ blue-green: switch traffic to the new environment instantly
✓ LOAD BALANCER + HEALTH CHECKS → route traffic only to healthy/ready instances;
new instances join only when READY (readiness checks)
✓ GRACEFUL SHUTDOWN → draining: stop sending new requests to an instance, let it FINISH
in-flight requests, THEN stop it (handle SIGTERM) → no dropped requests
✓ BACKWARD-COMPATIBLE changes → old and new versions coexist during the rollout
(API and DATABASE compatibility — expand-contract migrations)
