ipv4 diffserv entry

[Fred Portnoy]

First question, ipfw on FreeBSD 5.4-RELEASE. Other questions are more difficult, since we're dealing with a production network.... 

thanks

Fred Portnoy
Network Analyst
Plymouth State University

"unfettered by edgy modernisms, or classical influences"

----- Original Message -----
From: "Adrian Penisoara" <ady at freebsd.ady.ro>
To: "Fred Portnoy" <fportnoy at mail.plymouth.edu>
Cc: "freebsd-ipfw" <freebsd-ipfw at freebsd.org>
Sent: Tuesday, August 12, 2008 7:21:45 AM GMT -05:00 US/Canada Eastern
Subject: Re: ipv4 diffserv entry

Hi,

On Mon, Aug 11, 2008 at 10:30 PM, Fred Portnoy
<fportnoy at mail.plymouth.edu> wrote:
> By using Sniffer and tcpdump together, it appears that the entry in the "TOS" field of the IPv4 header is getting stripped off as the packet leaves the external facing interface of the firewall. Is this known behavior? Is there a way to preserve the TOS?

 Which firewall framework are we talking about (ipfw / pf / ipf) ?
Does it reproduce with all/other firewalls ?
 If you completely disable the firewall, does the issue stop reproducing ?

Regards,
Adrian.