This article was written in 2021. Versions, tools and recommendations may have changed since then. Newer posts are collected under .NET.
Our deployment ran smooth for weeks. But suddenly and without warning and only for one app, the “Bad Gateway” error appeared when deploying Azure DevOps to Azure App Service.
12021-10-02T18:22:51.9578529Z ##[section]Starting: Deploy to !!! PROD STAGE !!!
22021-10-02T18:22:51.9717826Z ==============================================================================
32021-10-02T18:22:51.9718244Z Task : Azure App Service deploy
42021-10-02T18:22:51.9718657Z Description : Deploy to Azure App Service a web, mobile or API app using Docker, Java, .NET, .NET Core, Node.js, PHP, Python or Ruby
52021-10-02T18:22:51.9719036Z Version : 4.184.4
62021-10-02T18:22:51.9719264Z Author : Microsoft Corporation
72021-10-02T18:22:51.9719571Z Help : https://aka.ms/azureappservicetroubleshooting
82021-10-02T18:22:51.9720056Z ==============================================================================
92021-10-02T18:22:52.5969763Z Got service connection details for Azure App Service:'mypage'
102021-10-02T18:23:54.6310344Z Package deployment using ZIP Deploy initiated.
112021-10-02T18:24:52.6365880Z ##[error]Failed to deploy web package to App Service.
122021-10-02T18:24:52.6380801Z ##[error]Error: Error: Failed to deploy web package to App Service. Bad Gateway (CODE: 502)
132021-10-02T18:24:53.9605307Z Successfully added release annotation to the Application Insight :mypage
142021-10-02T18:24:54.1466996Z ##[warning]Error: Failed to update deployment history. Error: Bad Gateway (CODE: 502)
152021-10-02T18:24:54.4910095Z App Service Application URL: https://myurl.azurewebsites.net
162021-10-02T18:24:54.5026817Z ##[section]Finishing: Deploy to !!! PROD STAGE !!!Spent a lot of time with Google on what this error could be. Many wrote to reset the App Service Plan, move the app to another region, but in the end it was very simple:
Just manually select a different app scale size (for example, from S1 to P1V3) and then switch back again. Suddenly everything worked again… ¯_(ツ)_/¯
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BEN ABT
Ben is Chief Engineering Officer and Principal Software Engineer at Medialesson.de, with a strong focus on .NET and Microsoft Azure. In his professional role, he designs and builds highly scalable platforms for hybrid and cloud-based scenarios. He also advises companies and C-levels on migrating to the sovereign cloud.
He runs myCSharp.de, the largest and most active German-speaking C# community forum, actively contributes to both his own and external open-source projects and regularly shares his knowledge through his blog, at community events, conferences and as a writer for technical magazines.
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