Subject: Re: TCP/IP problem in 1.2
To: None <firstname.lastname@example.org>
From: Jukka Marin <email@example.com>
Date: 07/17/1997 13:08:02
On Thu, Jul 17, 1997 at 11:49:03AM +0200, Stefan Grefen wrote:
> The TCP stack sets the DF flag (dont't fragment) so packets greater than
> MTU size will not be transmitted (netstat -p ip should show the as
> 'datagrams that can't be fragmented').
> The bug is in windows and on the merita system. Sending to destinations outside
> of the local network with DF set, an MSS > 512 and no dynamic MTU discovery is
> a call for trouble. (A lot of routers ignore the DF bit, thats the practical
> approach to ...)
Thanks for the detailed explanation. Now I understand what is happening.
Even better, I can tell that the bug is NOT in NetBSD :-))))
> I would patch the kernel to ignore the DF bit. Maybe this should become
> an sysctl option or an interface option.
This sounds like a good idea to me. Of course, the real bug should be fixed,
but there's only so much we can do to fix all the TCP/IP stacks in the world..
1503 kHz @ 22:30 EET DST Mon-Fri
---> http://www.jmp.fi/~jmarin/ <---