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AWS · 2 articles
TopicsAllDatabaseReal ProblemsAWSSystem Design
AWSAll in sectionLoad BalancingMessaging & QueuesScaling & Infra
AWSLoad Balancing·15 min read

Load Balancer Explained: L4 vs L7 — What the Door-Person Actually Sees

A simple, ground-up guide: L4 forwards raw TCP/UDP by IP and port, L7 opens the HTTP request and routes by URL, host, headers or cookies. Clear when-to-use-what for both basic and advanced scenarios (NLB+ALB stack, PrivateLink, gRPC, service mesh) plus a full AWS map — ALB, NLB, GWLB, CloudFront, API Gateway, Route 53, Global Accelerator — with gotchas around sticky sessions, client IP preservation, and WebSockets.

Load BalancingAWSNLBALBRead →

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AWS·Scaling & Infra

Why Your Autoscaling Isn't Working: The Truth About Spiky Traffic

Every type of scaling explained simply — horizontal, vertical, reactive, predictive, scheduled. Why HPA and ASG break on Dream11 during an IPL final, flash sales, and push notifications. Four real case studies (Dream11 IPL, OTT launch, ticketing fan-out, ETL sawtooth) with timelines, numbers, and the exact architectures that survived. If you've ever watched your p99 explode while HPA takes its sweet time — this is for you.

AutoscalingKubernetesHPA20 min read·
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