karn@petrus.UUCP (Phil R. Karn) (10/10/85)
A machine here has had a recurring problem that is about to drive us crazy. A VAX-11/780 running ULTRIX has several network interfaces: a PRONET, a 3-Com Ethernet, a dmr-11 and a DEC DEUNA. All work fine except the DEUNA. On a fairly regular basis, the machine becomes incapable of sending good IP packets out through the DEUNA, although it continues to receive them just fine. I suspect that packets are still going out with good Ethernet CRCs, except that their contents are garbled; the "bad IP header checksum" counts on other machines start increasing whenever the VAX attempts to send packets to them. Rebooting temporarily fixes the problem, for perhaps 12 hours or so. This problem is particularly aggravating because it prevents alternate routes through its other interfaces from being used. The fact that the DEUNA's receiver continues to work means that the router continues to believe that it can reach sites through that interface. Worse, it broadcasts this bogus information to sites on its other interfaces. Can anybody help? We're going to need toupees pretty soon. Phil
sdyer@bbncc5.UUCP (Steve Dyer) (10/15/85)
We've been using DEUNAs and LH/DH-11s on our VAX 780s and 785s with the
standard DEC Ultrix drivers without any problems similar to those you
describe. I should add that we do NOT run a kernel which supports
DECnet. I assume your field service people have given the DEUNA a clean
bill of health. If so, I suppose it may be a kind of data corruption,
perhaps induced by bugs in other drivers. You might want to eliminate
other drivers (such as DMR) and see whether you can discover any
correlation.
--
/Steve Dyer
{harvard,seismo}!bbnccv!bbncc5!sdyer
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