Zero-Downtime LB Upgrades and Maintenance.

Updated Apr 28, 2026

Short answer

Senior load balancing is about distributed systems architecture. It's not just about 'splitting traffic'; it's about global availability, extreme low-latency, and multi-layered security.

Deep explanation

Modern senior architects favor 'Cloud Native' patterns. We look at Anycast for global entry points, followed by L4 Maglev-style hashing for packet distribution, and L7 Envoy-based sidecars for fine-grained service mesh control. We utilize eBPF to bypass the traditional Linux networking stack (iptables) to achieve millions of packets per second on commodity hardware.

Real-world example

A global video streaming service using GSLB to route users to the nearest CDN node, with Anycast handling the initial IP reachability.

Common mistakes

  • Over-engineering a simple internal service with a complex service mesh when a basic Round-Robin LB would suffice.

Follow-up questions

  • What is the 'Double Proxy' problem?
  • How does ECMP work with Anycast?

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