Subject: Re: MTU
To: Nino Margetic <nino@cng.fr>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: port-pmax
Date: 12/07/2000 11:34:51
On Wed, Dec 06, 2000 at 10:09:42PM +0100, Nino Margetic wrote:
> > > Is there a way to change the MTU on the le0 interface??
> >
> > You should be able to lower it (e.g. ifconfig le0 mtu 512) but not increase
> > it over 1500.
> 
> from ifconfig man page:
> 
> mtu n           Set the maximum transmission unit of the interface to n.
>                 Most interfaces don't support this option.
> 
> from the shell:
> 
> nino kupa:/home/nino > sudo ifconfig -a
> Password:
> le0: flags=8b63<UP,BROADCAST,NOTRAILERS,RUNNING,PROMISC,ALLMULTI,SIMPLEX,MULTICAST>
> mtu 1500
>         address: 08:00:2b:bc:d6:c4
>         media: Ethernet manual
>         status: active
>         inet 192.168.100.5 netmask 0xffffff00 broadcast 192.168.100.255
> lo0: flags=8009<UP,LOOPBACK,MULTICAST> mtu 33200
>         inet 127.0.0.1 netmask 0xff000000
> ppp0: flags=8010<POINTOPOINT,MULTICAST> mtu 1500
> ppp1: flags=8010<POINTOPOINT,MULTICAST> mtu 1500
> ppp2: flags=8010<POINTOPOINT,MULTICAST> mtu 1500
> ppp3: flags=8010<POINTOPOINT,MULTICAST> mtu 1500
> sl0: flags=c010<POINTOPOINT,LINK2,MULTICAST> mtu 296
> sl1: flags=c010<POINTOPOINT,LINK2,MULTICAST> mtu 296
> sl2: flags=c010<POINTOPOINT,LINK2,MULTICAST> mtu 296
> sl3: flags=c010<POINTOPOINT,LINK2,MULTICAST> mtu 296
> nino kupa:/home/nino > sudo ifconfig le0 mtu 512
> ifconfig: SIOCSIFMTU: Invalid argument
> nino kupa:/home/nino >
> 
> Any (other? :-) suggestions?

No, sorry. This works fine with my tlp and epic interface, but also
fails for the le on my sparc and sun3. So this looks like a le-specific
problem.  I looked quickly at the code but didn't find anything obvious.

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