This is our old Q&A Site. Please post any new questions and answers at

I have a linux-based Firewall/Router (IPtables) in my network. When I change Default gateway of client to the Firewall, I can ping, traceroute, telnet 80 ... but can't browse via Browsers (IE, Chrome, FireFox without any proxy config). How can I analyse my tcp packet and understand the problem?

asked 08 Apr '14, 23:58

q12345's gravatar image

accept rate: 0%

but can't browse via Browsers (IE, Chrome, FireFox without any proxy config)

Maybe you just believe there is no proxy config, while there is one. What do you get if you run the following command on the client

telnet wpad 80


telnet wpad.your-internal-domain 80

Do you get a connection?

If so, please uncheck the following option in your browser and try again:

Firefox: Disable the option "Autodetect Proxy for this network" and select the option "no proxy".

Please read about Web Proxy Auto-Discovery Protocol (WPAD):

If wpad isn't an issue in your environment, please post a sample capture file somewhere (google drive, dropbox, and post the link here.

Furthermore check the firewall logs ;-))


permanent link

answered 09 Apr '14, 14:10

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
accept rate: 15%

Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here



Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text]( "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:


question asked: 08 Apr '14, 23:58

question was seen: 2,680 times

last updated: 09 Apr '14, 14:10

p​o​w​e​r​e​d by O​S​Q​A