W2k8 - DHCP option 252 problem

Hi all,

I've defined 252 DHCP option (DHCP) on our W2k8 DHCP server for autoconfig
proxy. However, it doesn't work.

In NetMon I've noticed that DHCP server DOES NOT send this option in DHCP
OFFER.

Isn't there some policy in W2k8 that could block the 252 option?

Thanks,
--
R.V.

I combine it with DNS. Not everything is going to be able to use the DHCP
method. You need it to work by both DNS and DHCP, and the two have to work
together.

First:
Create a CNAME entry in DNS called "wpad". Point it at the Host Record for
the Proxy Server.

Second:
Create the DHCP Option and point it at the DNS CNAME like this,
http://wpad.mydomain.loc

Third:
Configure the Proxy to "publish" its autoconfiguration script on port 80.
It *must* be port 80 or the DNS wpad setup will fail.
Open a web browser and go to the link http://wpad.mydomain.loc/wpad.dat
You should be prompted to Save or Open. Choose Open and you will see the
contents of the auto-configuration script.

http://www.google.com/search?hl=en&a...i=&safe=images

--
Phillip Windell
www.wandtv.com

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------


"Radovan Vojtek" <(E-Mail Removed)> wrote in message
news:6DB71588-91BB-44B5-98C5-(E-Mail Removed)...
> Hi all,
>
> I've defined 252 DHCP option (DHCP) on our W2k8 DHCP server for autoconfig
> proxy. However, it doesn't work.
>
> In NetMon I've noticed that DHCP server DOES NOT send this option in DHCP
> OFFER.
>
> Isn't there some policy in W2k8 that could block the 252 option?
>
> Thanks,
> --
> R.V.

Hello Philip,

thanks for your reply!

I cannot publish the wpad.dat on port 80 and I cannot use the the default
one from ISA - so that I modify the default one and create website on the
port 888. On the DHCP server I created 252 option for WPAD with
"http://1.2.3.4:888/wpad.dat" value accordint to the following technet
articles:

http://www.microsoft.com/technet/isa....mspx?mfr=true
http://www.microsoft.com/technet/isa....mspx?mfr=true
http://www.microsoft.com/technet/isa....mspx?mfr=true

I cannot use the DNS-based publishing of the wpad.dat. I need it for the
quarantine VLAN where are only non-domain computers with external DNS servers
defined (via DHCP) - so that there is no way to define wpad DNS entry with
the internal IP.

So my question is - how to force the W2k8 DHCP server to send the 252 option
in DHCP OFFER packets?

--
R.V.


"Phillip Windell" wrote:

> I combine it with DNS. Not everything is going to be able to use the DHCP
> method. You need it to work by both DNS and DHCP, and the two have to work
> together.
>
> First:
> Create a CNAME entry in DNS called "wpad". Point it at the Host Record for
> the Proxy Server.
>
> Second:
> Create the DHCP Option and point it at the DNS CNAME like this,
> http://wpad.mydomain.loc
>
> Third:
> Configure the Proxy to "publish" its autoconfiguration script on port 80.
> It *must* be port 80 or the DNS wpad setup will fail.
> Open a web browser and go to the link http://wpad.mydomain.loc/wpad.dat
> You should be prompted to Save or Open. Choose Open and you will see the
> contents of the auto-configuration script.
>
> http://www.google.com/search?hl=en&a...i=&safe=images
>
> --
> Phillip Windell
> www.wandtv.com
>
> The views expressed, are my own and not those of my employer, or Microsoft,
> or anyone else associated with me, including my cats.
> -----------------------------------------------------
>
>
> "Radovan Vojtek" <(E-Mail Removed)> wrote in message
> news:6DB71588-91BB-44B5-98C5-(E-Mail Removed)...
> > Hi all,
> >
> > I've defined 252 DHCP option (DHCP) on our W2k8 DHCP server for autoconfig
> > proxy. However, it doesn't work.
> >
> > In NetMon I've noticed that DHCP server DOES NOT send this option in DHCP
> > OFFER.
> >
> > Isn't there some policy in W2k8 that could block the 252 option?
> >
> > Thanks,
> > --
> > R.V.
>
>
>

"Radovan Vojtek" <(E-Mail Removed)> wrote in message
news:FBF43D79-0E16-43F4-8B94-(E-Mail Removed)...
> I cannot publish the wpad.dat on port 80 and I cannot use the the default
> one from ISA - so that I modify the default one and create website on the
> port 888. On the DHCP server I created 252 option for WPAD with
> "http://1.2.3.4:888/wpad.dat" value accordint to the following technet
> articles:

What happens when you use http://1.2.3.4:888/wpad.dat in a browser address
bar?


--
Phillip Windell
www.wandtv.com

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------

Hi Phillip,

> What happens when you use http://1.2.3.4:888/wpad.dat in a browser address bar?

I can access and download the wpad.dat file. It works fine in my test lab on
the W2k3 DHCP server - the 252 option is sent to the clients and use for
proxy autodiscovery. However in the production with W2k8 DHCP server it
doen's work as far as the 252 option is not send to the clients...

--
R.V.

I don't know then,...I don't use 2008

--
Phillip Windell
www.wandtv.com

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------

"Radovan Vojtek" <(E-Mail Removed)> wrote in message
news:F9E37A2C-140D-4ABC-8000-(E-Mail Removed)...
> Hi Phillip,
>
>> What happens when you use http://1.2.3.4:888/wpad.dat in a browser
>> address bar?
>
> I can access and download the wpad.dat file. It works fine in my test lab
> on
> the W2k3 DHCP server - the 252 option is sent to the clients and use for
> proxy autodiscovery. However in the production with W2k8 DHCP server it
> doen's work as far as the 252 option is not send to the clients...
>
> --
> R.V.
>
>