[vortex-bug] sporadic "eth0: Transmit error, Tx status register 82." Errors

Donald Becker becker@scyld.com
Mon, 31 Jul 2000 11:05:25 -0400 (EDT)

On 31 Jul 2000, Andi Hechtbauer wrote:

> >>>>> "DB" == Donald Becker <becker@scyld.com> writes:
>     DB> On 29 Jul 2000, Andi Hechtbauer wrote:
>     >> I'm using 3c59x.c:v0.99H 11/17/98 Donald Becker with two 3Com
>     >> 3C905B 100bTX (rev 48) NICs in a AMD-K6(tm) 3D /400 Linux
>     >> 2.2.12 Machine.
>     DB> ...
>     >> Since then I'm seeing sporadic "eth0: Transmit error, Tx status
>     >> register 82." Messages in our logs, and reading the list
>     >> archive I found this may be caused by various things:
>     DB> 0x82 Out of window collision.  This typically occurs when some
>     DB> other Ethernet host is incorrectly set to full duplex on a
>     DB> half duplex network.
> Hm, well, since I don't have access to the other boxes on this
> lan, I might have to discuss that with my ISP... Is there a way
> to find out which host is configured incorrectly (could I or my
> ISP spot the culprit using some kind of packet sniffer)?

Not easily.  The errant host is transmitting its header while another
machine is transmitting, so the header from the misconfigured machine is
always corrupted.  The usual way to locate the problem is a TCP performance
test against every local machine.  But the misconfigured machine is usually
the one you don't know about.

Another case study of the problems that forced-full-duplex causes...

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Beowulf Clusters / Linux Installations
Annapolis MD 21403