The DigitalOcean team successfully scaled their managed load balancer product to support over 1 million connections, improving scalability and performance for customers. The original architecture used a single Droplet with a reserved IP, but this was replaced by a more scalable solution using a passthrough network load balancer (NLB) deployed on bare metal servers. The NLB leverages BGP and ECMP to distribute traffic across multiple servers, ensuring high availability and reducing the need for complex VPC management. Katran, an eBPF program, sits between the NIC and kernel networking stack, enabling highly performant packet processing. The new architecture allows customers to scale their load balancers with predictable pricing and redundancy, providing a consistent product experience as they evolve their deployments.