[2185] in linux-net channel archive
Re: IP forwarding bug in 1.3.73
daemon@ATHENA.MIT.EDU (Todd Graham Lewis)
Wed Mar 20 22:36:51 1996
To: submit-linux-dev-net@ratatosk.yggdrasil.com
From: Todd Graham Lewis <tlewis@mindspring.com>
Date: Wed, 20 Mar 1996 22:13:27 -0500
In-Reply-To: <199603141542.QAA05959@bolyai.cs.elte.hu>
On Thu, 14 Mar 1996, Zoltan Hidvegi wrote:
> We have a ppp dial-in server running linux-1.3.73. Normally it uses 296
> MRU/MTU on the ppp interfaces and 1500 MTU on the ethernet card.
> Unfortunately it cannot forward UDP packages larger that 296 bytes correctly.
>
> When I raise the MTU on the ppp line to 1500 everything works fine.
Why does everyone insist on running such a small mtu on their ppp
connections? Larger mtu's are tougher to tweak, but everyone should be
aiming at the largest mtu they can handle, and rarely do you really have
to bump it below 1000. Smaller mtu's will cause excessive fragmentation,
with end-to-end mtu discovery, they place a much larger load on the
intervening routers, which almost always includes the backbone routers,
which are _way_ overburdened as it is, and it decreases performance.
I simply do not understand why people insist on doing this. If there is
a reason, could someone please clue me in to the big secret?
Todd
____________________________________________________________________________
| |
|Todd Graham Lewis Core Engineering Mindspring Enterprises, Inc.|
|tlewis@mindspring.com (800) 719 4664|
|__________________________________________________________________________|
