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From: Archie Cobbs <archie@tribe.com>
Message-Id: <199512142247.OAA00963@bubba.tribe.com>
Subject: Re: MTU/MRU in 'User Mode' PPP???
To: combssf@salem.ge.com (Stephen F. Combs)
Date: Thu, 14 Dec 1995 14:47:37 -0800 (PST)
Cc: questions@freebsd.org
In-Reply-To: <199512142024.PAA25229@combs.salem.ge.com> from "Stephen F. Combs" at Dec 14, 95 03:24:44 pm
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> Is there any way to set the MTU(Max Transmission Unit[Size]) and/or MRU
> (Max Receive Unit[Size]) on the 'tun' device for 'User Mode' PPP (ijppp??)?
> 
> These 1500byte MTU/MRU sizes are killing me....
> 
> Kernel Mode PPP allows this, but I haven't seen anything on MTU/MRU with
> User Mode.....(and yes, I did look!).

I'm not 100% certain about this, but I believe you must recompile the
kernel with a higher setting of the value for TUNMTU, defined in the
header file "/usr/src/sys/net/if_tun.h" in order to pass > 1500 byte
packets to the tunnel interface.

Then say "set mru 1800" or whatever to ppp. Also check out the definitions
in "/usr/src/usr.sbin/ppp/hdlc.h".

-Archie

_______________________________________________________________________________
Archie L. Cobbs, archie@tribe.com  *  Tribe Computer Works http://www.tribe.com