възловото приложение на azure от време на време пренасочва към server.js

Имам приложение Node.js (Express), което работи в услугата за приложения на Azure. От време на време, когато посещавам своя домейн, вместо да изпълня приложението Node, ще бъда отведен до https://example.com/server.js. Това не се случва често, но понякога ще имаме потребителски доклад, че не могат да стигнат до нашето приложение и това в крайна сметка се оказва виновникът.

За да влошат нещата, е много трудно, ако не и невъзможно, да се възпроизведе. Имах известен късмет при възпроизвеждането с нова инсталация на нов браузър, но не винаги.

По принцип използвам web.config по подразбиране с няколко добавени реда за HSTS/HTTPS. Виж отдолу:

<?xml version="1.0" encoding="utf-8"?>
<!--
     This configuration file is required if iisnode is used to run node processes behind
     IIS or IIS Express.  For more information, visit:

     https://github.com/tjanczuk/iisnode/blob/master/src/samples/configuration/web.config
-->

<configuration>
  <system.webServer>
    <!-- Visit http://blogs.msdn.com/b/windowsazure/archive/2013/11/14/introduction-to-websockets-on-windows-azure-web-sites.aspx for more information on WebSocket support -->
    <webSocket enabled="false"/>
    <handlers>
      <!-- Indicates that the server.js file is a node.js site to be handled by the iisnode module -->
      <add modules="iisnode" name="iisnode" path="server.js" verb="*"/>
    </handlers>
    <rewrite>
      <rules>
        <!-- Do not interfere with requests for node-inspector debugging -->
        <rule name="NodeInspector" patternSyntax="ECMAScript" stopProcessing="true">
          <match url="^server.js\/debug[\/]?"/>
        </rule>

        <!-- First we consider whether the incoming URL matches a physical file in the /public folder -->
        <rule name="StaticContent">
          <action type="Rewrite" url="public{REQUEST_URI}"/>
        </rule>

        <!-- All other URLs are mapped to the node.js site entry point -->
        <rule name="DynamicContent">
          <conditions>
            <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="True"/>
          </conditions>
          <action type="Rewrite" url="server.js"/>
        </rule>

        <!-- Redirect all HTTP to HTTPS -->
        <rule name="HTTP to HTTPS redirect" stopProcessing="true">
          <match url="(.*)"/>
          <conditions>
            <add ignoreCase="true" input="{HTTPS}" pattern="off"/>
          </conditions>
          <action redirectType="Permanent" type="Redirect" url="https://{HTTP_HOST}/{R:1}"/>
        </rule>
      </rules>

      <outboundRules>
        <rule enabled="true" name="Add Strict-Transport-Security when HTTPS">
          <match pattern=".*" serverVariable="RESPONSE_Strict_Transport_Security"/>
          <conditions>
            <add ignoreCase="true" input="{HTTPS}" pattern="on"/>
          </conditions>
          <action type="Rewrite" value="max-age=31536000"/>
        </rule>
      </outboundRules>

    </rewrite>

    <!-- 'bin' directory has no special meaning in node.js and apps can be placed in it -->
    <security>
      <requestFiltering>
        <hiddenSegments>
          <remove segment="bin"/>
        </hiddenSegments>
      </requestFiltering>
    </security>

    <!-- Make sure error responses are left untouched -->
    <httpErrors existingResponse="PassThrough"/>

    <!--
      You can control how Node is hosted within IIS using the following options:
        * watchedFiles: semi-colon separated list of files that will be watched for changes to restart the server
        * node_env: will be propagated to node as NODE_ENV environment variable
        * debuggingEnabled - controls whether the built-in debugger is enabled

      See https://github.com/tjanczuk/iisnode/blob/master/src/samples/configuration/web.config for a full list of options
    -->
    <!--<iisnode watchedFiles="web.config;*.js"/>-->
  </system.webServer>
</configuration>

Някакви предложения защо това може да се случи?