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From: Archie Cobbs <archie@whistle.com>
Message-Id: <199612022228.OAA19080@bubba.whistle.com>
Subject: Re: Bizarro bug in 2.1.6 that's had me stumped for ages...
In-Reply-To: <336.849531953@time.cdrom.com> from "Jordan K. Hubbard" at "Dec 2, 96 05:05:53 am"
To: jkh@time.cdrom.com (Jordan K. Hubbard)
Date: Mon, 2 Dec 1996 14:28:28 -0800 (PST)
Cc: hackers@FreeBSD.org
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> I have a gateway machine with an SMC8216 ethernet card in it and an
> ISDN TA hanging off a standard 16550 serial port.  It works just
> peachy, 99.9% of the time, except after I've really exercised it in
> some way (seems to happen most frequently after a make world though
> this could just be the sheerest coincidence).  The symptom is that
> it's suddenly unable to talk to its SLIP interface directly, e.g.:
> 
> root@whisker-> ifconfig -a
> ..
> sl0: flags=9011<UP,POINTOPOINT,LINK0,MULTICAST> mtu 552
>         inet 204.216.27.194 --> 204.216.27.193 netmask 0xfffffff0 
> 
> root@whisker-> ping 204.216.27.193
> PING 204.216.27.193 (204.216.27.193): 56 data bytes
> <zilch, nada, zip>
> 
> The weirder thing is that it still functions just great as a gateway.
> On another machine, which it talks to (just fine) through its ethernet
> interface, I can say:
> 
> jkh@time-> ping 204.216.27.193
> PING 204.216.27.193 (204.216.27.193): 56 data bytes
> 64 bytes from 204.216.27.193: icmp_seq=0 ttl=254 time=113.731 ms
> 
> No problem.  This is going, after one hop, out the very same SLIP
> interface that whisker refused to talk to in the previous example.

I'd guess it's an ARP problem, possibly on the remote end of the
link (since you're using proxy arp there .. correct?).

More generally, one or the other side has lost a route I bet.

-Archie

___________________________________________________________________________
Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com