using Fiddler with localhost .... how to?

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gerry_lowry (alliston ontario canada (705) 250-0112)

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Mar 21, 2010, 9:16:55 PM3/21/10
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Hello,

from time to time, I would like to peek at the same type of information
provided by Fiddler2 when I'm testing a web site with local iis 5.1 on
winXP pro sp3, iis 7.5 on win2008, or even with the vs2008 "ASP.NET Development Server"
or its close relative "Cassin Web Server".

problem is that localhost http traffic does not show up in Fiddler2 ...
I'm guessing that's by design.

I'm also assuming that there's a simple procedure to enable Fiddler2
to NOT ignore localhost traffic. What is it, please?


Thank you.
Gerry

EricLaw

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Mar 21, 2010, 9:59:32 PM3/21/10
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Indeed: http://www.fiddler2.com/fiddler/help/hookup.asp#Q-LocalTraffic

On Mar 21, 6:16 pm, "gerry_lowry \(alliston ontario canada \(705\)

gerry_lowry (alliston ontario canada (705) 250-0112)

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Apr 14, 2010, 4:20:34 PM4/14/10
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Thank you, Eric. A colleague taught me another trick that SOMETIMES works
(although I am unsure BOTH why it works and why is does not work):

place a period after localhost

http://weblogs.asp.net/lorenh/archive/2008/01/10/tip-for-using-fiddler-on-localhost.aspx
from "Loren Halvorson's Blog"

Loren writes:
"This tip is widely known and documented" at http://www.fiddler2.com/Fiddler/help/knownissues.asp.
Loren's link leads to http://www.fiddler2.com/Fiddler/help/hookup.asp#Q-LocalTraffic
which is the one that you mentioned.

HOWEVER, the trick of adding a period, e.g.: http://localhost.:49572, seems to have been lost from the fiddler2.com site.

Testing with the Visual Studio ASP.NET Development Server, with Fiddler v2.2.8.6,
using this trick of placing a period WORKS on my Window 2003 Server
BUT on my Windows 2008 Web Server R2, IE8, I get this error:

[Fiddler] Connection to localhost failed.
Exception Text:
No connection could be made because the target machine actively refused it :: 1.49572

I'm unsure as to why it is NOT working on my win2008 server; it is NOT a firewall issue
because I get the same FAIL result on win2008 when I turn the firewall OFF.

Gerry

P.S.: the simple PERIOD after "localhost" is a GOOD trick WHEN it works.

----- Original Message -----
From: "EricLaw" bay...@gmail.com To: "Fiddler" <httpf...@googlegroups.com>
Sent: Sunday, March 21, 2010 9:59 PM
Subject: [Fiddler] - 1943 Re: using Fiddler with localhost .... how to?

Indeed: http://www.fiddler2.com/fiddler/help/hookup.asp#Q-LocalTraffic

EricLaw

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Apr 14, 2010, 4:29:12 PM4/14/10
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The "trailing dot after localhost" trick was deliberately dropped from
the Fiddler2.com documentation because it is inferior to the
alternative.

http://ipv4.fiddler/ will work much better, for a number of reasons,
including this one:

> I'm unsure as to why it is NOT working on my win2008 server; it is NOT a firewall issue
> because I get the same FAIL result on win2008 when I turn the firewall OFF.

It's not working on your Win2k8 server because your Win2k8 server
supports IPv6, so when you do a DNS lookup for "localhost.", you get
back [::1, 127.0.01]. However, the ASP.NET development server doesn't
actually listen on the IPv6 interface, and hence when you try to
connect to it, you get the connection failure message.

If you use http://ipv4.fiddler interface, however, Fiddler knows to
map that to "127.0.0.1" on the IPv4 interface and you're good to go.

An "experimental" alternative you may wish to play with can be found
in the upcoming Fiddler 2.2.9 build: https://www.fiddler2.com/dl/fiddler2alphasetup.exe

On the Tools > Fiddler Options > Connections tab, you can tick the
"Use PAC Script" box. When you do that and restart, you will find that
WinINET/IE will send even http://localhost/ requests to Fiddler, and
no address changes are required.

On Apr 14, 1:20 pm, "gerry_lowry \(alliston ontario canada \(705\)


250-0112\)" <gerry.lo...@abilitybusinesscomputerservices.com> wrote:
> Thank you, Eric.  A colleague taught me another trick that SOMETIMES works
>                            (although I am unsure BOTH why it works and why is does not work):
>
>          place a period after localhost
>

> http://weblogs.asp.net/lorenh/archive/2008/01/10/tip-for-using-fiddle...


>        from "Loren Halvorson's Blog"
>
> Loren writes:  
>

> "This tip is widely known and documented" athttp://www.fiddler2.com/Fiddler/help/knownissues.asp.
> Loren's link leads tohttp://www.fiddler2.com/Fiddler/help/hookup.asp#Q-LocalTraffic

> > Gerry- Hide quoted text -
>
> - Show quoted text -

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