Subject: Re: can't raise in kernel pppoe0 with mtu > 1460
To: Alicia da Conceicao <alicia@engine.ca>
From: Martin Husemann <martin@duskware.de>
List: tech-net
Date: 03/21/2005 10:10:33
On Mon, Mar 21, 2005 at 03:58:46AM -0500, Alicia da Conceicao wrote:
> For some reason, whenever I attempt to increase the MTU on my in kernel
> pppoe interface beyond 1460, it fails:

It does not allow you a MTU setting greater that what the ppp ipcp
negotiation said your peer would accept. Bring the link down, set mtu high,
check mtu and bring the link back up. You'll probably see a higher mtu with
the link down, but as soon as it goes up, it will be at the value your peer
requested.

Of course there could be a bug in there, so you may check the ppp negotiation
with tcpdump (or ifconfig pppoe0 debug).

Martin