ARP packets lost with Netgear FA310TX?

Dave Platt dplatt@radagast.org
Tue May 18 23:12:36 1999


} I haven't yet worked out what would happen in tulip.c if this condition
} occurs (that is, if tulip.c would log a warning or increment an error count,
} or would simply discard the packet).  Any opinions in that regard?

Our experience here at TiVo is that when this bug hits, the tulip.c
driver becomes confused, logs several errors (packets overrunning from
one DMA buffer to the next) and then ceases processing any subsequent
packets.  You have to shut down and then restart the interface to get
the card to "hear" again.  Ungood.

I've been tempted to hack in a more simple workaround for the problem
(just drop the packets and let TCP etc. handle the retransmission) but
haven't had time yet.

Interestingly enough, we've seen far fewer of these problems, even
under conditions of very heavy packet traffic, since we switched from
a hub-based network to an entirely-switched 100BaseT net (a couple of
weeks ago).  I suspect that the packet mishandling problem may occur
only when there are network anomalies (e.g. collisions during
transmission, or packets garbled during reception due to a collision
elsewhere on the network) and that the PNIC chip may work OK as long
as the network is "clean".