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Date: Wed, 29 Jan 1997 21:59:48 -0800 (PST)
From: Dmitry Kohmanyuk <dk@dog.farm.org>
Message-Id: <199701300559.VAA03336@dog.farm.org>
To: shocking@mailbox.uq.edu.au (Stephen Hocking)
Cc: freebsd-hackers@freebsd.org
Subject: Re: Setting MTU from userland ppp
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In article <199701290935.TAA01388@mailbox.uq.edu.au> you wrote:
> How does one do this? If I try fiddling tun0 (ifconfig tun0 mtu 256) the 
> userland ppp get quite cranky and ppp net connections  hang.

set mtu 576

in /etc/ppp/ppp.conf

works for me.

This would specify your _tranimission_ size.  To change it on the other
side, change the other end's setup.

Don't use 256 as your MTU.  (violates the RFC)