Wednesday, February 25, 2009

IIS7 and net.tcp only WAS hosting

I was interested in having net.tcp-only hosting (no HTTP) for a WAS-activated WCF service in IIS7. I found that IIS uses icons that trick you into thinking the site is in an error state when in reality it is not. Here are the steps I took to host my service:

Create the Website

I didn't want to use a virtual directory to host my service, so I created a new web site in IIS Manager (right-click Sites, then Add Web Site). The key here is to select the net.tcp binding type and specify the port in the Binding Information section:

After doing this, IIS7 will show the website in what appears to be an error state (it will have a red 'X' next to the website icon and many of the right-panel Actions menu options (notably the entire Manage Web Site section, containing the restart/start/stop controls and Advanced Settings link) will not appear. THIS SEEMS TO BE A RED HERRING. It will show the red 'X' whenever there are no HTTP bindings for the service. Here is what it looked like on a different site I set up in this manner:

The service will function in spite of the fact that it doesn't show as started. Starting/stopping the service must be done via the controls on the site's application pool (right-clicking it works):

Add Filesystem Components

At a minimum, you need your .svc file, a web.config file, and a bin folder containing the assembly(ies) that implement your service in the website root folder:

The .svc file simply contains the declaration of the class that implements the service:
<%@ServiceHost language="c#" Debug="true" Service="Microsoft.ServiceModel.Samples.CalculatorService" %>
In the web.config, you can omit all references to HTTP bindings, and set up the Metadata Exchange (mex) endpoint to use the net.tcp binding. You can even omit that if you don't need the service to be discoverable, although it helps to retain it:
<?xml version="1.0" encoding="utf-8" ?>

        <endpoint    address=""
                    contract="Microsoft.ServiceModel.Samples.ICalculator" />
        <endpoint    address="mex"
                    contract="IMetadataExchange" />

    <!--For debugging purposes set the includeExceptionDetailInFaults attribute to true-->
        <behavior name="CalculatorServiceBehavior">
          <serviceMetadata /> <!--You do not need this node if you remove the mex endpoint-->
          <serviceDebug includeExceptionDetailInFaults="False" />
Note that I did not specify any port information in the address for the endpoint using netTcpBinding as I wanted it to simply use the binding specified for the website (in the case of the website I showed creating up top, TCP over port 11111).

Create a Client

After this, you should be able to point to the service via net.tcp and generate a proxy. In Visual Studio 2008, you can use the Add Service Reference facility in your client project by specifying the following, substituting your service's TCP port for the '11111':


  1. It doesn't work unless you add net.tcp to EnabledProtocols on Advanced settings and you can't get to Advanced settings unless you add an http binding. I added the http binding but I don't have the http binding defined in the web.config and I was able to add the net.tcp. Once I did that then I could get to the metadata and also call via net.tcp

  2. Thanks for this, it helped me get things running the way I wanted.

    Kenneth is right that you need to add an HTTP binding in order to get to the advanced settings to add net.tcp as an allowed protocol.

    Once you do that and test that the service is working you can remove the HTTP binding. The icon will go back to a red X but the service will now work correctly without the HTTP binding.