From High Availability to a Real Plan B: Lessons from the Latest AWS Outage and a Practical Guide
AWS’s October 20 outage reminded us of a simple truth: resilience can’t be improvised. High availability (HA) within a single region helps, but it doesn’t replace a plan B that keeps services running when the common element too many components depend on fails (region, control plane, DNS, queues, identity, etc.). This guide lays out a