Generating 'Fragment Needed but DF was Set' ICMP & Dummynet

Alexander Motin mav at
Mon Feb 23 10:03:53 PST 2004

Andre Oppermann wrote:

> Alexander Motin wrote:
>>Here are my patches for this problem for FreeBSD 4.8 and 5.2.
>>Review them please.
> Doing a mcopy is pretty ugly... but ip_output() doesn't offer any way
> of saying "don't flush packet but leave it for icmp error messages".
> So the better fix would be to teach that to ip_output() and change
> the callers accordingly.  Actually I'll have a patch to do that ready
> in a couple of hours.  Then I'll commit your patch w/o the packet
> copying stuff.

This was taken from ip_forward(). :) If you say that it can be reworked 
here then it can be reworked there too for increasing performance.

Alexander Motin mav at
ISP "Alkar-Teleport"

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