Subject: Re: PPP and flow control
To: Mike Long <>
From: None <>
List: current-users
Date: 01/20/1996 08:47:46
At 14:50 1/17/96, Mike Long wrote:
>I'm still having problems sending data over my PPP link.  I can
>receive data or send *small* amounts of data without difficulty
>(e.g. sup works); but any attempt to send a chunk of data over a
>certain limit fails.  The only possible explanation I think likely is
>that flow control is broken.  I am running an i386 -current system; my
>PPP link runs on my 14.4kbps modem.
>I experimented with ping's -s flag last night.  While pinging a
>machine 3 hops away over a PPP link:
>64 byte packets: 0% failure
>128 byte packets: 0% failure
>256 byte packets: 0% failure
>384 byte packets: 38% failure
>512 byte packets: 100% failure
>Anything over 512 bytes also has 100% failure.
>I first ran into trouble after I switched from gcc 2.4.5 to 2.7.2, but
>my current kernel was built with -fno-strength-reduce.
>Can anyone give me any pointers as to how I can diagnose and debug
>this problem?
>Mike Long <> 
>VLSI Design Engineer         finger for PGP public key
>Analog Devices, CPD Division          CCBF225E7D3F7ECB2C8F7ABB15D9BE7B
>Norwood, MA 02062 USA       (eq (opinion 'ADI) (opinion 'mike)) -> nil

Have you checked to ensure that the MTU being used on BOTH ends of the link
are set to the same amount?