How do I monitor all incoming http requests?

Solution 1:

What you need to do is configure Fiddler to work as a "reverse proxy"

There are instructions on 2 different ways you can do this on Fiddler's website. Here is a copy of the steps:

Step #0

Before either of the following options will work, you must enable other computers to connect to Fiddler. To do so, click Tools > Fiddler Options > Connections and tick the "Allow remote computers to connect" checkbox. Then close Fiddler.

Option #1: Configure Fiddler as a Reverse-Proxy

Fiddler can be configured so that any traffic sent to http://127.0.0.1:8888 is automatically sent to a different port on the same machine. To set this configuration:

Start REGEDIT
Create a new DWORD named ReverseProxyForPort inside HKCU\SOFTWARE\Microsoft\Fiddler2.
Set the DWORD to the local port you'd like to re-route inbound traffic to (generally port 80 for a standard HTTP server)
Restart Fiddler
Navigate your browser to http://127.0.0.1:8888

Option #2: Write a FiddlerScript rule

Alternatively, you can write a rule that does the same thing.

Say you're running a website on port 80 of a machine named WEBSERVER. You're connecting to the website using Internet Explorer Mobile Edition on a Windows SmartPhone device for which you cannot configure the web proxy. You want to capture the traffic from the phone and the server's response.

Start Fiddler on the WEBSERVER machine, running on the default port of 8888.
Click Tools | Fiddler Options, and ensure the "Allow remote clients to connect" checkbox is checked. Restart if needed.
Choose Rules | Customize Rules.
Inside the OnBeforeRequest handler, add a new line of code:
if (oSession.host.toLowerCase() == "webserver:8888") oSession.host = "webserver:80";
On the SmartPhone, navigate to http://webserver:8888

Requests from the SmartPhone will appear in Fiddler. The requests are forwarded from port 8888 to port 80 where the webserver is running. The responses are sent back through Fiddler to the SmartPhone, which has no idea that the content originally came from port 80.

Solution 2:

I would install Microsoft Network Monitor, configure the tool so it would only see HTTP packets (filter the port) and start capturing packets.

You could download it here

Solution 3:

Configure Fiddler as a 'reverse proxy' on Windows

(for Mac, see the link in Partizano's comment below)

I know there's already an answer suggesting this, however I want to provide the explanation and instructions for this that Telerik should have provided, and also cover some of the 'gotchas', so here goes:

What does it mean to configure Fiddler as a 'reverse proxy'?

By default, Fiddler only monitors outgoing requests from the machine on which you're running Fiddler
To monitor incoming requests, you need to configure Fiddler to work as a 'reverse proxy'
What this means is that you need to set Fiddler up as a 'proxy' that will intercept incoming http requests that are sent to a specific port (8888) on the machine where you want to listen to the incoming requests. Fiddler will then forward those requests to the web server on the same machine by sending them to the usual port for http requests (usually port 80 or 443 for https). It's actually very quick and easy to do!
The standard way to set this up with Fiddler is to get Fiddler to intercept all request sent to Port '8888' (since this won't normally be used by anything else, although you could just as easily use another port)
You then need to use the registry editor to get Fiddler to forward any http requests that Fiddler receives on port 8888, so that they're forwarded to the standard http port (port 80, port 443 for an https request, or another custom port that your web server is set to listen on)

NOTE: For this to work, any request you want to intercept must be sent to port 8888

You do this by appending :8888 to your hostname, for example like this for an MVC route:

http://myhostname:8888/controller/action

Walkthrough

Ensure Fiddler can accept remote http requests on port 8888:

Run Fiddler as administrator Go to Tools > Fiddler Options > Connections, and ensure that 'Allow remote computers to connect' is checked, and 'Fiddler listens on port' is set to 8888:

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Configure Fiddler to forward requests received on port 8888 to port 80

Close Fiddler
Start REGEDIT
Create a new DWORD named ReverseProxyForPort inside HKEY_CURRENT_USER\SOFTWARE\Microsoft\Fiddler2.
- Now set the DWORD value to the local port you'd like to re-route inbound traffic to (generally port 80 for a standard HTTP server)
To do this, right-click the DWORD you created and select 'Modify'. Ensure 'Base' is set to 'Decimal' and enter '80' (or another port) as the 'Value data':

Ensure that port 8888 is opened on the firewall

You must ensure that port 8888 is open to external requests (it won't be by default if your server is firewall-protected)

That's it! Fiddler should now be set up as a reverse proxy, to intercept all requests from port 8888 (so that you can view them in Fiddler), and it will then forward them to your web server to actually be handled.

Test a request

Restart Fiddler
To test that Fiddler is intercepting external requests, open a browser on the same machine where you've set up Fiddler as a reverse proxy. Navigate your browser to http://127.0.0.1:8888
This tests making a basic request to to port 8888
You should see the request intercepted by Fiddler
Now you can test a request from another machine, for example by making a request from a browser on another machine like this (where 'remoteHostname' is a hostname on the machine where you've set up Fiddler as a reverse proxy) :

http://remoteHostname:8888/controller/action

Alternatively, you can compose a request by using another instance of Fiddler on a remote machine, using a URL similar to the one above. This will allow you to make either a GET or a POST request.

IMPORTANT: Once you've finished viewing your request(s), go back to Tools > Fiddler Options > Connections and remove the 'Allow remote computers to connect' option, otherwise 3rd parties will be able to bounce traffic through your server

Solution 4:

Guys found the perfect way to monitor ALL traffic that is flowing locally between requests from my machine to my machine:

Install Wireshark
When you need to capture traffic that is flowing from a localhost to a localhost then you will struggle to use wireshark as this only monitors incoming traffic on the network card. The way to do this is to add a route to windows that will force all traffic through a gateway and this be captured on the network interface.

To do this, add a route with <ip address> <gateway>:
```
 cmd> route add 192.168.20.30 192.168.20.1
```
Then run a capture on wireshark (make sure you select the interface that has bytes flowing through it) Then filter.

The newly added routes will come up in black. (as they are local addresses)

Solution 5:

Microsoft Message Analyzer is the successor of the Microsoft Network Monitor 3.4

If your http incoming traffic is going to your web server at 58000 port, start the Analyzer in Administrator mode and click new session:

use filter: tcp.Port = 58000 and HTTP

trace scenario: "Local Network Interfaces (Win 8 and earlier)" or "Local Network Interfaces (Win 8.1 and later)" depends on your OS

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