How One Developer Achieved Zero-Downtime Deploys on a Single EC2 Instance

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A developer running a WiFi hotspot platform on a single EC2 instance faced nearly two minutes of downtime during deployments, causing failed payment webhooks and lost customer internet access. Rather than migrating to Amazon ECS or EKS, which would add complexity and cost unsuitable for a small single-region platform, the developer implemented a blue/green deployment strategy using Docker Compose. The approach uses two identical container slots, where only one serves live traffic at a time, and a new slot must pass a health check before the proxy switches traffic to it. Any failure before the switch automatically keeps the previous version live, ensuring uninterrupted service. The method relies on Docker Compose YAML anchors, container health checks, and an atomic proxy reload to achieve zero-downtime releases without additional infrastructure.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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