On Mon, Jul 23, 2001 at 12:42:14AM +0200, Herb Peyerl wrote:
> Manuel Bouyer <bouyer@antioche.lip6.fr>  wrote:
>  > > Initially I used an mtu of '296' and started seeing the problem. So I
>  > > bumped it down to 250 out of curiosity ... 
>  > > 
>  > > Later I bumped the mtu up to '502' (some random number higher than 250)
>  > > and it all works fine.
>  > > 
>  > > So what am I missing? Shouldn't this all be independant of the mtu/mru?
>  > > Or is there some sysctl I'm missing?
>  > 
>  > Maybe it's just that the other (ppp) end doesn't propely fragment big packets ?
> 
> The other end is a DMS-500 phone switch that I have no control of. 
> 
>  > Did you try to turn on path MTU discovery on both host ?
>  > sysctl -w net.inet.ip.mtudisc=1
> 
> you mean my jornada running pppd and the 20 hop away machine with
> sshd?  or you mean both ends of the ppp connection?  

No, both end of the ssh connection. If the DMS-500 fails to fragment
pakets, maybe at last it properly returns an ICMP need-frag for such
packets ...

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
--