Fiddler introduces 504 Gateway Timeout

[RSP]

When connecting direct with a particular website/request, everything runs happily, but as soon as Fiddler is introduced into the equation, a 504 Gateway Timeout occurs.

The request in question is an http request on port 443.

Is it an issue that can be fixed?

[RSP]

This is running either .net2 or .net4 version on Windows 7 32-bit PC.

[EricLaw]

Is the URL public so we can look at it?
Is the "http request on port 443" a CONNECT TUNNEL request?
Have you enabled HTTPS decryption in Fiddler?
Is there a message on the Log tab?

My current guess is that you're hitting this: http://blogs.msdn.com/b/fiddler/archive/2012/03/29/https-request-hangs-.net-application-connection-on-tls-server-name-indicator-warning.aspx

[RSP]

Hi EricLaw

Unfortunately not
No, it's a POST of the format http://website:443/blah
Yes, and no. Both results in the same error
Nothing of note. A "[Fiddler] No HTTP request was received from (iexplore:780) new client socket, port 25203.", but this seems innocuous.

The link is almost the opposite of my issue.

I've persuaded the powers-that-be to allow a direct route to this host which will solve my problem that I was trying to use Fiddler to diagnose. Obviously the error still exists whilst using Fiddler, but it is no longer important to me in this instance. I am able to perform testing if this is being addressed, however.

Thanks for your response.

[EricLaw]

Your code is performing an unencrypted HTTP post to the HTTPS port (443) and that works correctly? That's a very oddly-configured server.

Are you sure that your company's proxy server permits such traffic? Many upstream proxy servers (e.g. those that Microsoft had on their corporate network) refused traffic that was trying to "sneak out" through HTTPS ports.

The message "No HTTP request was received" commonly occurs for exactly the reason cited in the blog post-- the client fails to establish a secure connection with the HTTPS site and thus closes the connection.

[Michael]

I can confirm this. Today I was submitting a WebRequest in C# to a PHP file that I am running on GoDaddy shared hosting.

All initial requests are successful, but while Fiddler is running, each second request results in a 504 Gateway Timeout error.

As soon as I close Fiddler, I can hit the URL repeatedly without error.

I am running my tests on Windows Server 2012 Standard

Fiddler Version:

Fiddler Web Debugger (v4.4.6.1)
Built: Thursday, February 20, 2014

64-bit AMD64, VM: 33.00mb, WS: 58.00mb
.NET 4.0.30319.17929 WinNT 6.2.9200.0

You've run Fiddler: 4 times.

Running on: systemic:8888
Listening to: All Adapters
Gateway: Auto-Config
Offline/disabled

Send feedback to: [e-mail]
©2014 Telerik. All rights reserved.

[P.J. Keukens]

Hi Here,
We've got the same problem with the new version 4.4.6.1 64-bit AMD64, .net 4.0. We have been using the old version (before 4.4.6.1) for about two months with great success, it was a brilliant tool. Good speed en calls to the webservices never failed.

The problems started with the new version 4.4.6.1, it gives 504 error's quite often. Even on simple posts without message body we get 504. It's to such an extent that the tool isn't really usable anymore. When we take fiddler out of the equasion everything runs fine again.

The message we get from Fiddler is:
[Fiddler] ReadResponse() failed: The server did not return a response for this request. Server returned 0 bytes.

Fiddler also gives this message in the header: Cache-Control: no-cache, must-revalidate 
This is happening with all 504 errors and I think has something todo with it.

The server does respond and is okay so it's something todo with Fiddler and it's very anoying. We don't have a public url for the webservice so I can't help with that.

Is there a possibillity we can download the old version for the time being?  

Cheers Patrick       

[AndreasW]

Hi,
I can aslo confirm the 504 gateway timeouts.

The problem started after updating to version v2.4.6.1
After reverting to v2.4.5.0, everything works again.

[Jason]

We've upgraded today as well to 4.4.6.2 and started getting the same 504 errors. Is this timeout related? Is there a property that can be set somewhere like in the "older version" to help (i.e. like "fiddler.network.timeouts.serverpipe.receive.initial") ?

[John]

I have the same issue under v2.4.6.1, and this never happend until I updated days ago.
I tried replaced with SampleRules.js but still happens.
It seems only POST requests get random 504 errors immediately after been issued.

[Eric Lawrence]

Your first step should be to upgrade to the latest version of Fiddler (v2.4.6.2 or later). If that doesn't help, then please send a SAZ file using Help > Send Feedback in Fiddler.

thanks,



-Eric Lawrence

[Gomain]

I'm having this similar problem. I'm using...

Fiddler Web Debugger (v4.4.8.3)<br>Built: 05 June 2014<br><br>64-bit AMD64, VM: 96.00mb, WS: 125.00mb<br>.NET 4.0.30319.17929 WinNT 6.1.7601 SP1

I am loading a page that consists of multiple Ajax calls that load parts of the page. All from the same host. It so happens that all the Ajax calls timeout at 30 seconds and returns...

HTTP/1.1 504 Fiddler - Receive Failure<br>Date: Fri, 06 Jun 2014 09:10:54 GMT<br>Content-Type: text/html; charset=UTF-8<br>Connection: close<br>Cache-Control: no-cache, must-revalidate<br>Timestamp: 16:10:54.727<br><br>[Fiddler] ReadResponse() failed: The server did not return a response for this request. Server returned 0 bytes.

Searches from here and here recommend setting preference fiddler.network.timeouts.serverpipe.receive.initial , but it seems to have been deprecated. Adding it in about:config does not fix things either. I went ahead and added fiddler.network.timeouts.serverpipe.receive.reuse too, still doesn't help.

I've noticed other sessions that take up to 55 seconds in the timeline. So I'm suspecting this is only an Ajax behavior.

The page can load normally without fiddler.

What am I missing?

Please help.

[EricLaw]

How long does the request in question take to return a response when Fiddler /isn't/ running?

[Gomain]

This is getting absurd. It turned out that my server was actually, for some still unknown reason, randomly closes connections at 30s. The fact that it happened only when connecting through Fiddler was a pure coincidence. Sorry for the false alarm.

Anyhow, adding fiddler.network.timeouts.serverpipe.receive.initial and fiddler.network.timeouts.serverpipe.receive.reuse to about:config does work.

Thanks for the support. :)

[Hamed]

Hi everyone,

I use Fiddler to connect Windows 10 Metro apps through proxy. 

I have downloaded a game from Windows store, but when I run it, it cannot connect to Internet and I get 504 Result. 

Can anyone help me what to do?