3C905B-TX and 3Com dual speed hub work only after reboot

Michael Gengenbach Michael_Gengenbach@compuserve.com
Wed Dec 2 12:54:59 1998


I have a strange problem with my new 3Com OfficeConnect dual speed hub
and 3Com 3C905B-TX NICs under Linux (it works ok with Microsoft
Windows NT 4.0):

After the hub is powered on and I boot my Linux box it starts ok,
synchronizes at 100 MBit (according to the hub), but can't communicate
to another device on the hub (namely a Cisco 1603 router at 10 Mbit).
It seems that the ARP packages which the Linux box sends out are not
answered. BTW, the hardware address is shown correctly and not all FF.

Only after I reboot my Linux box (I can even disconnect it from the
power) it starts like before, but this time everything works. When
I switch off the hub now and then back on again it will still work
(the first packages in a continous ping will get lost, though).

Do you have any idea what could be the cause? Might it be a problem
with the hub? I don't think so because when I boot my PC under
Windows NT 4.0 right after I power on both the hub and the PC everything
works (I just checked this behaviour 3 times in a row).

In the archive I could find a similar message last month under the
title "3C905 & HUB switch-on":

> When I switch-off and then switch-on my HUB, the card doesn't go
> on-line again [3C905 100Mbps (manual full-duplex & speed)]. Under
> NetWare everything seems to be ok. Any advice/solutions? (I don't
> want to reload module).

But I could find no solution in the thread.

Here is my setup:

I use SuSE-Linux V5.3 with a 2.0.35 kernel and tried both the 0.99E
driver supplied by SuSE and the 0.99G driver from CESDIS. The result
is about the same, but despite I use "options 3c59x options=4" and
/var/log/messages reads
   "Media override to transceiver type 4 (100baseTX)"
with the 0.99G driver the Linux box synchronizes only to 10 MBit
the second time (i.e. after the reboot when the driver works).

0.99E synchronizes to 100 MBit both times (the initial boot when
it doesn't work and the reboot when it starts working).
As I said when booting with Windows NT 4.0 it works every time
right at the first boot.

The hub is a 8-port 3Com OfficeConnect Dual Speed Hub which can't
be configured (to my knowledge) and my second test device was a
Cisco 1603 router running IOS 11.3 at 10 MBit. I did also test
with an older SuSE Linux and I believe a 0.99C driver with the
same results.

As I said: any help is appreciated, because we want to buy a larger
quantity of this NIC. Just in case there is no solution, do you
have any proposition of a better 10/100 MBit NIC which will not
be replaced soon with a more problematic one (like the 3C905 was
with the 3C905B)?

Thanks in advance