Last Updated: 22 Sep 2021 13:35 by Leonardo
Created on: 02 Dec 2019 23:49
Type: Bug Report
Can't capture traffic to "localhost"?

Simple as that: fiddler everywhere does not capture traffic to localhost, AND when you insert your local address, it captures your request only to return that "

[Fiddler] DNS Lookup for "www." failed. System.Net.Internals.SocketExceptionFactory+ExtendedSocketException Device not configured



MAC OSX, using safari.

Other address are captured as expected

Posted on: 22 Sep 2021 13:35
tks @Nick Iliev
Nick Iliev
Posted on: 22 Sep 2021 07:57

Hi Leonardo,



I just wanted to let you know that Fiddler Everywhere now automatically adds the loopback expectation on macOS, and thus, the localhost traffic can now be captured by default.


Nick Iliev
Progress Telerik

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Eric R | Senior Technical Support Engineer
Posted on: 09 Dec 2019 14:29

Hi Leonardo,

Thank you for providing this information. Although, in order to fully investigate we'll need more information. Is it possible to provide the following information?

1. Steps to Reproduce. Note that this should provide a detailed explanation of the scenario. For example, we'll need to know things like what type of application is hosted on localhost, is it using HTTPS/SSL, are you using the composer or just listening on the wire, etc.

2. Safari Version.

3. MacOS Version.

4. Screenshots of logs or error output.

5. Screenshots of the System Network Proxy configuration when Fiddler Everywhere is running and when it is not.

6. Any other screenshots that might be relevant.

Once we have the above information, we'll be able to start reviewing the Bug Report.

In the meantime, please let me know if you need any additional information. As always, thank you for your feedback.


Eric R | Technical Support Engineer
Progress Telerik

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