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Date: Thu, 14 Aug 1997 17:10:52 -0400
From: "Donald J. Maddox" <dmaddox@scsn.net>
To: Nick Johnson <spatula@gulf.net>
Cc: freebsd-questions@FreeBSD.ORG
Subject: Re: bad fcs problem in pppd and ijppp
Reply-To: dmaddox@scsn.net
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In-Reply-To: <Pine.BSI.3.96.970814070202.15775B-100000@pompano.pcola.gulf.net>; from Nick Johnson on Thu, Aug 14, 1997 at 07:08:13AM -0500
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On Thu, Aug 14, 1997 at 07:08:13AM -0500, Nick Johnson wrote:
> I've run into a few problems with both ijppp and pppd.  During periods of
> increased modem activity (so it seems) FCS errors are reported (as HDLC
> errors in ijppp) and the link becomes unusable.  pppd reports about 50
> such errors and then the link gets terminated.
> 
> I've tried the obvious things; reducing the connect speed, port speed,
> double-checking the flow control, etc.  No useful results.
> 
> What is interesting is that this only seems to be a problem when
> connecting with a digital box.  It shows up both with our Ascend Max and
> our Portmaster 3.  It doesn't seem to ever happen when connecting to a
> PM2e and an analog modem.  I've double-checked the configurations on our
> digital boxen, and they are configured to use RTS/CTS only, just like my
> side of the connection.
> 
> As I was writing this, during a period of relatively low activity, pppd
> reported another FCS error and disconnected.
> 
> Is anyone familiar with this problem or have any similar experience or
> insight?

    I am seeing the exact same thing since my ISP changed over to an
all digital system with Ascend MAX 4004s and DM-12 Modem cards.  Wish I
had some insight for you, but I've been stumped by this one for a while
now :-(