Linux box causing network meltdown! HELP!!!

Harvey J. Stein (hjstein@bfr.co.il)
20 Jul 1999 01:35:13 +0300


My linux box (RH 6.0 with RH supplied kernel, version 2.2.5) is
putting a weird packet out the ethernet port which is causing a Cisco
ethernet switch to go insane, spewing out packets wildly & bringing
the network down. This isn't exactly wining lots of friends for Linux
over here. I also can reproduce this effect fairly easily, at least I
could until my box was banned from the net for this!

Here's a hex dump of the packet:

01 80 C2 00 00 01 00 A4 00 80 D2 9C 88 08 00 01
40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00

The network guys here got that from a sniffer they put on the line.
They say the weird things about the packet are the ethertype of 8808,
that it's shorter than the minimum packet size of 64 bytes, and that
it's a multicast broadcast packet. So, why my box is putting it on
the wire (especially given that I'm not doing any multicast), and how
do I stop it? BTW, rebuilding the kernel without multicast support
doesn't stop these weird packets from going out.

Hardware details:

A Compaq deskpro EN. PII 450 with 100mhz bus speed. dmesg has this
to say about the ethernet:

The PCI BIOS has not enabled this device! Updating PCI command
0003->0007.
eth0: Invalid EEPROM checksum 0x60fe, check settings before activating this device!
eth0: Intel EtherExpress Pro 10/100 at 0x2000, 00:A4:00:80:D2:9C, IRQ 11.
Receiver lock-up bug exists -- enabling work-around.
Board assembly 800080-000, Physical connectors present:
Primary interface chip None PHY #0.
General self-test: passed.
Serial sub-system self-test: passed.
Internal registers self-test: passed.
ROM checksum self-test: passed (0x04f4518b).
Receiver lock-up workaround activated.

Thanks,

-- 
Harvey J. Stein
Bloomberg LP
hjstein@bfr.co.il

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/