Programming Tutorials

  Intermittent 502 Bad Gateway errors are among the most frustrating issues to debug in a production environment. Your application traffic is flowing normally, but occasionally, HTTP requests fail with a generic 502. You check your application logs, only to find no trace of the failed request. This happens because the failure occurred at the infrastructure or runtime boundary, before your Node.js application could log the transaction. To effectively troubleshoot Azure Web App 502 errors, you must look beyond your application code and understand the Azure platform architecture bridging your traffic. This guide explores the architectural root causes of these errors and provides concrete, modern solutions to stabilize your Node.js deployments. The Architecture Behind Azure App Service 502 Bad Gateway Azure App Service utilizes a front-end load balancer called Application Request Routing (ARR). The ARR routes incoming external traffic to the worker instances hosting your application. A...