High availability (HA) tegese ngrancang sistem supaya tetep operasional sanajan ana kegagalan — liwat redundancy, multi-AZ deployment, auto-recovery, lan ngilangke single points of failure. Iki goal fundamental kanggo sistem production lan area kunci ing AWS architecture.
Core HA principles
✓ ELIMINATE SINGLE POINTS OF FAILURE — no single component whose failure takes down
the system → redundancy everywhere (multiple instances, AZs, etc.)
✓ Deploy across MULTIPLE AVAILABILITY ZONES — survive an AZ (data center) failure
✓ AUTOMATIC RECOVERY — detect failures and recover/replace automatically (no manual fix)
✓ DECOUPLE components — failures isolated; one component's failure doesn't cascade
