title: Error R10 (Boot timeout) > Web process failed to bind to $PORT within 90 seconds of launch
body: <p>I'm deploying an Docker image with CMD line in it :</p>
  
  <pre><code>CMD ["java","-XX:+UnlockExperimentalVMOptions","-XX:+UseCGroupMemoryLimitForHeap","-Djava.security.egd=file:/dev/./urandom","-Dspring.server.port=$PORT","-Dserver.port=$PORT","-jar","/life-project.jar"]
  </code></pre>
  
  <p>while in the log it looks like :</p>
  
  <pre><code>2018-08-06T10:51:17.489612+00:00 heroku[web.1]: Starting process with command java -XX:\+UnlockExperimentalVMOptions -XX:\+UseCGroupMemoryLimitForHeap -Djava.security.egd\=file:/dev/./urandom -Dspring.server.port\=\48227 -Dserver.port\=\48227 -jar /life-project.jar
  </code></pre>
  
  <p>with the following error :</p>
  
  <pre><code>2018-08-06T10:51:26.106011+00:00 app[web.1]: ***************************
  2018-08-06T10:51:26.106012+00:00 app[web.1]: APPLICATION FAILED TO START
  2018-08-06T10:51:26.106014+00:00 app[web.1]: ***************************
  2018-08-06T10:51:26.106015+00:00 app[web.1]:
  2018-08-06T10:51:26.106017+00:00 app[web.1]: Description:
  2018-08-06T10:51:26.106018+00:00 app[web.1]:
  2018-08-06T10:51:26.106020+00:00 app[web.1]: Failed to bind properties under 'server.port' to java.lang.Integer:
  2018-08-06T10:51:26.106021+00:00 app[web.1]:
  2018-08-06T10:51:26.106022+00:00 app[web.1]: Property: server.port
  2018-08-06T10:51:26.106024+00:00 app[web.1]: Value: $PORT
  2018-08-06T10:51:26.106025+00:00 app[web.1]: Origin: "server.port" from property source "systemProperties"
  2018-08-06T10:51:26.106026+00:00 app[web.1]: Reason: failed to convert java.lang.String to java.lang.Integer
  2018-08-06T10:51:26.106028+00:00 app[web.1]:
  2018-08-06T10:51:26.106029+00:00 app[web.1]: Action:
  2018-08-06T10:51:26.106030+00:00 app[web.1]:
  2018-08-06T10:51:26.106032+00:00 app[web.1]: Update your application's configuration
  </code></pre>
  
  <p>What should I change in the configuration?</p>