Re: proxy.pac -- Proxy Auto-Config File Format

[Ralf Gesel|ensetter <rgx@gmx.de>]

Hi Jonas, 

I don't understand exactly what to change - and where - is this 
the /etc/dhcp3/dhcpd.conf ? And ... (see below)


Am Mittwoch, 6. Oktober 2004 00:04 schrieb Jonas Smedegaard:
> Here's a dhcp3 server snippet I use for my setups:
>
> # Web Proxy Auto-Discovery Protocol (described in RFC 3040, used in
> # Microsoft Internet Explorer 5.0 and later and maybe Mozilla).
> option wpad-url                 code 252 = text;

what is this ^^  for?
>
> # Sample domain config
>
> # Beware that Microsoft Internet Explorer resolves hostname ahead,
> # (A record if CNAME record provided, and raw IP if A record
> provided), # so use the default web host if serving name-based
> virtual hosts. #option auto-proxy-config      \ 
"http://wpad.example.net/wpad.pac";;

so, this should read http://tjener.intern/prox.pac  without the 
comments?

Sorry for my ignorance,
regards
Ralf

P.S.: I did some research to fill in the holes in my knowledge (and 
hopefully, that of others, too):

WPAD: Acronym for Web Proxy Autodiscovery Protocol.

If your DomainName is machine.something.meta.net.nz then 
InternetExplorer will request the following urls1? until it finds a 
WPAD configuration file.

    *
      [link]http://wpad.something.meta.net.nz/wpad.dat
    *
      [link]http://wpad.meta.net.nz/wpad.dat
    *
      [link]http://wpad.net.nz/wpad.dat
----
Other alternatives include (subst. host.co.nz for your hostname):

The DHCP method (the MicrosoftCorporation "preferred option", which like 
most MSFT'isms, doesn't actually work). Add the following to 
your /etc/dhcpd.conf

  option option-252               "!http://wpad.host.co.nz/proxy.pac";;

With ISC DHCP v3+, 'option-#' options don't work, You have to do this in 
the global section of your configuration:

  option wpad-url               code 252 = text;                          
(define a new option)

And add this in either the global or appropriate subnet section(s) of 
your configuration:

  option wpad-url               "!http://wpad.host.co.nz/proxy.pac";;       
(use new option)
----
The DNS method(s). Add all or some of the follwing entries to your DNS 
zone file.

 $ORIGIN host.co.nz.
 wpad            IN      A       192.168.0.254
                 IN      TXT     "service: 
wpad:!http://wpad.host.co.nz:80/proxy.pac";
 wpad.tcp        IN      SRV     0 0 80 wpad.host.co.nz.
----
src: http://www.wlug.org.nz/WPAD