TMG is Unable to Listen on Port 80 (no IIS was not installed)

TMG is Unable to Listen on Port 80 (no IIS was not installed)

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Introduction
Consider the scenario where a TMG 2010 Server is installed as Hyper-V guest on a Windows 2008 Server. You publish a website on port 80 or enable HTTP to HTTPS redirection on a Web Listener for an existing SSL publishing rule. When you try to access the published website you get an error: 10060 Connection Refused.

Troubleshooting
A quick look at the TMG Live Logging reveals the following:

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Netstat output indicates that Process ID 4 (System) is listening on port TCP 80 as shown below:

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This explains why Firewall Service was not able to bind itself to TCP port 80.In scenarios where IIS is installed on the same machine as the ISA/TMG Servers and IIS binds itself to port 80, it is common to such output. As part of the troubleshooting for issues of this nature, we checked and found that IIS was not installed on the TMG Server. We then used Process Explorer to check if any other process which hooks into System process was causing this behaviour and found that it was not the case.

We then used the netsh command line interface to check the state of HTTP Service with the following command:

image

Based on the above output, we can see that WSMAN is listening on port 80. WSMAN (Web Services-Management) is an open standard for SOAP based protocol management of servers, application and web services. WinRM (Windows Remote Management) is Microsoft’s implementation of WS-Management standard.

In this particular case the Windows Remote Management service was grabbing port 80 on the TMG guest machine which is why the Web Proxy service was not able to bind itself to port 80 and therefore, requests from external clients were failing. Disabling the Windows Remote Management service or changing the WinRM listener to listen on a port other than 80 resolved this issue.

Conclusion
This post explains a scenario where a service other than IIS grabs web ports used by TMG causing publishing rules to fail. In case connection to a particular port on TMG is failing, always check if TMG is listening on that port.

Authors
Junaid Ahmad Jan
Security Support Engineer
Microsoft CSS Forefront Security Edge Team

Mohit Kumar
Senior Security Support Escalation Engineer
Microsoft CSS Forefront Security Edge Team

Technical Reviewer
Yuri Diogenes
Senior Security Support Escalation Engineer
Microsoft CSS Forefront Security Edge Team

Comments
  • telnet localhost 80 returns HttpAPI/2.0 which in turn means to "Sql server reporting service". Stopping the same releases port 80.

  • Thank you very much. I was able to find out that sql server reporting service is using port 80 using above command.

  • Very good and helpful article,. not only for TMG it helps on other servers also...

    Hey Ori thanks Mate..

    Cheers!

    Sanjay

  • this was extremely helpful.  We were running Mail marshal Reporting Console on the TMG 2010 server.  if you disable IIS servers and SQL reporting services, it works

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