Next.js App Failing to Start in Azure App Service

Hi Tariq Ghouri

Thank you for posting your question on the Microsoft Q&A forum. 

From your description, I understand that your Azure App Service container is repeatedly failing to start. The logs indicate that the container exits during startup and does not respond to HTTP pings on port 8080. As a result, warmup requests time out after approximately 50–73 seconds, causing Azure to stop the site. Internal container logs are not available, which makes it challenging to identify the root cause. 

Based on the details provided, here are a few suggestions that may help: 

1. Verify Application Port Configuration:  Ensure that your application is listening on port 8080, as Azure App Service uses this port for health checks. If your application listens on a different port, configure the WEBSITES_PORT application setting in Azure App Service to match your application’s listening port. 
2. Increase Startup Time Limit:  Consider increasing the container startup time limit by adding the application setting WEBSITES_CONTAINER_START_TIME_LIMIT (up to a maximum of 1800 seconds). This can help if your application requires additional time to initialize before responding to requests. 

For additional guidance, you can refer to the official documentation here:  Configure custom containers for Azure App Service 

Feel free to post back if you have any further questions or need assistance with implementing these changes. 

@Vimal Lalani Thanks for the response. I have updated the suggested values in Azure Portal --> Azure App service --> Settings --> Environment Variables --> App Settings but still log stream shows that the application is trying to ping port 8080 and it is still failing. Below are the updated logs.
2025-08-11T07:42:37.322Z INFO - Starting container for site2025-08-11T07:42:37.328Z INFO - docker run -d --expose=8080 --name web-dev_0_de547d25 -e WEBSITE_USE_DIAGNOSTIC_SERVER=true -e WEBSITES_PORT=3000 -e WEBSITE_SITE_NAME=inzo-web-dev -e WEBSITE_AUTH_ENABLED=False -e WEBSITE_ROLE_INSTANCE_ID=0 -e WEBSITE_HOSTNAME=web-dev-acb4cwh3atg3btez.canadacentral-01.azurewebsites.net -e WEBSITE_INSTANCE_ID=9dead3715cfabf4121227c7b50ed47ff10d83fa4ce409893ec6050f6aee91951 -e NODE_OPTIONS=--require /agents/nodejs/build/src/Loader.js appsvc/node:20-lts_20250724.2.tuxprod REDACTED 2025-08-11T07:42:37.331Z INFO - Logging is not enabled for this container.Please use https://aka.ms/linux-diagnostics to enable logging to see container logs here. 2025-08-11T07:42:40.825Z INFO - Initiating warmup request to container web-dev_0_de547d25 for site web-dev 2025-08-11T07:42:57.424Z INFO - Waiting for response to warmup request for container web-dev_0_de547d25. Elapsed time = 16.6038622 sec 2025-08-11T07:43:15.689Z INFO - Waiting for response to warmup request for container web-dev_0_de547d25. Elapsed time = 34.8687336 sec 2025-08-11T07:43:33.595Z INFO - Waiting for response to warmup request for container web-dev_0_de547d25. Elapsed time = 52.774797 sec 2025-08-11T07:43:54.952Z INFO - Waiting for response to warmup request for container web-dev_0_de547d25. Elapsed time = 74.131307 sec 2025-08-11T07:42:39.356750415Z _____ 2025-08-11T07:42:39.356795561Z / _ \ __________ _________ ____ 2025-08-11T07:42:39.356801243Z / /\ \__ / | _ __ _/ __
2025-08-11T07:42:39.356805985Z / | / /| | /| | /\ / 2025-08-11T07:42:39.356810452Z _|__ /_____ __/ || ___ > 2025-08-11T07:42:39.356815451Z / / / 2025-08-11T07:42:39.356820193Z A P P S E R V I C E O N L I N U X 2025-08-11T07:42:39.356824601Z 2025-08-11T07:42:39.356828756Z Documentation: http://aka.ms/webapp-linux 2025-08-11T07:42:39.356832975Z NodeJS quickstart: https://aka.ms/node-qs 2025-08-11T07:42:39.356837254Z NodeJS Version : v20.19.3 2025-08-11T07:42:39.356841460Z Note: Any data outside '/home' is not persisted 2025-08-11T07:42:39.356845867Z 2025-08-11T07:42:49.653898853Z Starting OpenBSD Secure Shell server: sshd. 2025-08-11T07:42:49.695651475Z WEBSITES_INCLUDE_CLOUD_CERTS is not set to true. 2025-08-11T07:42:49.785471941Z Updating certificates in /etc/ssl/certs... 2025-08-11T07:43:04.084184095Z rehash: warning: skipping ca-certificates.crt,it does not contain exactly one certificate or CRL 2025-08-11T07:43:04.237316378Z 4 added, 0 removed; done. 2025-08-11T07:43:04.238861236Z Running hooks in /etc/ca-certificates/update.d... 2025-08-11T07:43:04.298585555Z done. 2025-08-11T07:43:04.298613087Z CA certificates copied and updated successfully. 2025-08-11T07:43:04.627747662Z Starting periodic command scheduler: cron. 2025-08-11T07:43:04.897455404Z Found build manifest file at '/home/site/wwwroot/oryx-manifest.toml'. Deserializing it... 2025-08-11T07:43:04.927489322Z Could not find operation ID in manifest. Generating an operation id... 2025-08-11T07:43:04.927514244Z Build Operation ID: c695a3ef-c318-4313-b7ac-2e789247e2cd 2025-08-11T07:43:05.547768417Z Environment Variables for Application Insight's IPA Codeless Configuration exists.. 2025-08-11T07:43:05.605773219Z Writing output script to '/opt/startup/startup.sh' 2025-08-11T07:43:05.835218403Z Running #!/bin/sh 2025-08-11T07:43:05.835245846Z 2025-08-11T07:43:05.835251217Z # Enter the source directory to make sure the script runs where the user expects 2025-08-11T07:43:05.835255885Z cd "/home/site/wwwroot" 2025-08-11T07:43:05.835260424Z 2025-08-11T07:43:05.835264627Z export NODE_PATH=/usr/local/lib/node_modules:$NODE_PATH 2025-08-11T07:43:05.835269009Z if [ -z "$PORT" ]; then 2025-08-11T07:43:05.835273480Z export PORT=8080 2025-08-11T07:43:05.835278165Z fi 2025-08-11T07:43:05.835282302Z 2025-08-11T07:43:05.835286469Z echo Found tar.gz based node_modules. 2025-08-11T07:43:05.835307379Z extractionCommand="tar -xzf node_modules.tar.gz -C /node_modules" 2025-08-11T07:43:05.835312145Z echo "Removing existing modules directory from root..." 2025-08-11T07:43:05.835316463Z rm -fr /node_modules 2025-08-11T07:43:05.835320748Z mkdir -p /node_modules 2025-08-11T07:43:05.835324961Z echo Extracting modules... 2025-08-11T07:43:05.835329181Z $extractionCommand 2025-08-11T07:43:05.835333318Z export NODE_PATH="/node_modules":$NODE_PATH 2025-08-11T07:43:05.835337684Z export PATH=/node_modules/.bin:$PATH 2025-08-11T07:43:05.835341889Z if [ -d node_modules ]; then 2025-08-11T07:43:05.835346194Z mv -f node_modules _del_node_modules || true 2025-08-11T07:43:05.835350436Z fi 2025-08-11T07:43:05.835354516Z 2025-08-11T07:43:05.835358611Z if [ -d /node_modules ]; then 2025-08-11T07:43:05.835362880Z ln -sfn /node_modules ./node_modules 2025-08-11T07:43:05.835367180Z fi 2025-08-11T07:43:05.835371333Z 2025-08-11T07:43:05.835375430Z echo "Done." 2025-08-11T07:43:05.842723789Z PATH="$PATH:/home/site/wwwroot" npm start 2025-08-11T07:43:05.852507705Z Found tar.gz based node_modules. 2025-08-11T07:43:05.863778221Z Removing existing modules directory from root... 2025-08-11T07:43:05.943645795Z Extracting modules... 2025-08-11T07:43:55.044423038Z Done. 2025-08-11T07:43:57.818127947Z npm info using npm@10.9.2 2025-08-11T07:43:57.818168307Z npm info using node@v20.19.3 2025-08-11T07:43:59.373786763Z 2025-08-11T07:43:59.373830660Z > nextjs@0.1.0 start 2025-08-11T07:43:59.373836148Z > next start -p $PORT 2025-08-11T07:43:59.373840754Z 2025-08-11T07:44:03.153730037Z node:internal/modules/cjs/loader:1215 2025-08-11T07:44:03.174310487Z throw err; 2025-08-11T07:44:03.174323358Z ^ 2025-08-11T07:44:03.174327985Z 2025-08-11T07:44:03.174332717Z Error: Cannot find module '../server/require-hook' 2025-08-11T07:44:03.174337111Z Require stack: 2025-08-11T07:44:03.174341303Z - /node_modules/.bin/next 2025-08-11T07:44:03.174345654Z at Module._resolveFilename (node:internal/modules/cjs/loader:1212:15) 2025-08-11T07:44:03.174350021Z at Module._load (node:internal/modules/cjs/loader:1043:27) 2025-08-11T07:44:03.174354310Z at Module.require (node:internal/modules/cjs/loader:1298:19) 2025-08-11T07:44:03.174358716Z at Module.patchedRequire [as require] (/agents/nodejs/node_modules/diagnostic-channel/dist/src/patchRequire.js:16:46) 2025-08-11T07:44:03.174363172Z at require (node:internal/modules/helpers:182:18) 2025-08-11T07:44:03.203875874Z at Object.<anonymous> (/node_modules/.bin/next:6:1) 2025-08-11T07:44:03.203901876Z at Module._compile (node:internal/modules/cjs/loader:1529:14) 2025-08-11T07:44:03.203907866Z at Module._extensions..js (node:internal/modules/cjs/loader:1613:10) 2025-08-11T07:44:03.203920860Z at Module.load (node:internal/modules/cjs/loader:1275:32) 2025-08-11T07:44:03.203926193Z at Module._load (node:internal/modules/cjs/loader:1096:12) { 2025-08-11T07:44:03.203930718Z code: 'MODULE_NOT_FOUND', 2025-08-11T07:44:03.203935069Z requireStack: [ '/node_modules/.bin/next' ] 2025-08-11T07:44:03.203939418Z } 2025-08-11T07:44:03.203943709Z 2025-08-11T07:44:03.203947920Z Node.js v20.19.3 2025-08-11T07:44:03.203952218Z npm http fetch GET 200 https://registry.npmjs.org/npm 654ms 2025-08-11T07:44:03.302667578Z npm notice 2025-08-11T07:44:03.302691648Z npm notice New major version of npm available! 10.9.2 -> 11.5.2 2025-08-11T07:44:03.302697204Z npm notice Changelog: https://github.com/npm/cli/releases/tag/v11.5.2 2025-08-11T07:44:03.302701774Z npm notice To update run: npm install -g npm@11.5.2 2025-08-11T07:44:03.302706368Z npm notice 2025-08-11T07:44:05.409Z ERROR - Container web-dev_0_de547d25 for site web-dev has exited, failing site start 2025-08-11T07:44:05.446Z ERROR - Container web-dev_0_de547d25 didn't respond to HTTP pings on port: 8080. Failing site start. See container logs for debugging. 2025-08-11T07:44:05.527Z INFO - Stopping site web-dev because it failed during startup.

Additionally for the information, Yes the applistens on port 3000 and the same has been configured in app settings as you suggested.