For high-availability deployments, we leverage Fly.io's global Anycast network and DNS-based health checks. When a machine in region A goes offline, Fly's Anycast routing automatically directs traffic to healthy machines in other regions without manual intervention.
For intra-region redundancy, we deploy 2 nodes per region in HA mode. If one node fails, traffic is seamlessly routed to the other node in the same region through Fly.io's internal load balancing. This provides N+1 redundancy within each region, ensuring service continuity even during single-node failures.