Undeliverable UDP broadcasts crashing Linux 2.0.x?

Franz Sirl (franz.sirl@lauterbach.com)
Thu, 31 Oct 1996 12:40:06 +0100


Hi,

in our site we have just upgraded our network. Due to this the cabling to
the Linux was switched from BNC to TP. The TP cable is connected to a 10
Mbit port of a 10/100Mbit switch. This switch is turned off overnight.

Ever since this network change the Linux was down the next morning. I
looked a little bit into it, and I now think that it's either the network
card driver (tulip.c v0.32,v0.37,v0.41) or an internal problem with UDP
broadcasts.
There are two broadcast sources (telling from netstat -an) running on that
machine, the SAMBA server and the MoreCOM software (a FaxModem Server for
Windows clients).
It seems Linux crashes as soon as the Send-Q on the socket reaches the 64k
region. This happens due to the physically down network and the continously
running UDP broadcast sources Samba and MoreCOM (about 1 packet/min).

Unfortunately the only log I get is from tulip.c, so I don't know what's
really the cause:

Oct 31 01:17:30 linuxpc1 kernel: eth1: transmit timed out, switching to AUI
media.
Oct 31 01:18:20 linuxpc1 kernel: eth1: transmit timed out, switching to
10baseT media.
Oct 31 01:18:30 linuxpc1 kernel: eth1: transmit timed out, switching to AUI
media.
Oct 31 01:19:30 linuxpc1 kernel: eth1: transmit timed out, status fc360000,
SIA ffffffc0 ffffef0d ffff87c5 ffff0006, resetting...
Oct 31 01:19:30 linuxpc1 kernel: Rx ring 00fff428: 80000000 80000000
80000000 80000000 80000000 80000000 80000000 80000000 800000
00 80000000 80000000 80000000 80000000 80000000 80000000 80000000
Oct 31 01:19:30 linuxpc1 kernel: Tx ring 00fff528: 7fffb178 80000000
80000000 80000000 80000000 80000000 80000000 80000000
Oct 31 01:20:30 linuxpc1 kernel: eth1: transmit timed out, status fc360000,
SIA ffffffc0 ffffef0d ffff87c5 ffff0006, resetting...
Oct 31 01:20:30 linuxpc1 kernel: Rx ring 00fff428: 80000000 80000000
80000000 80000000 80000000 80000000 80000000 80000000 800000
00 80000000 80000000 80000000 80000000 80000000 80000000 80000000
...

The crash doesn't happen with BNC cabling.

My setup:
Pentium120
Linux 2.0.2[34]
2 * SMC8432 with 21040, one connected to the internet, the other to the
internal network.

Any hints?
Franz Sirl.

Franz Sirl

!!!>> Come and visit Bavaria!!
!!!>> Enjoy the alps, original bavarian beergardens and much more!

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