Problem with 3C905B-TX 10/100 adapter

Rich Schaaf rschaaf@pingtel.com
Sun Jul 25 11:44:57 1999


I have a PC running the RedHat 6.0 distribution and using a 3Com
3C905B-TX 10/100 NIC.  Details about the PC's configuration are included
below.

The Linux box and a router are the only two hosts on their LAN segment. 
This segment is implemented using a Netgear DS104 10/100 hub.

Because the router and the Linux box are the only two hosts on the
segment, and because the Linux box uses the network infrequently, there
are long periods of network inactivity on the segment.  After about 20
minutes of network inactivity, the link light goes out on the port of
the hub that is connected to the NIC card of the Linux PC.  I've tried
moving the connection to different ports on the 10/100 hub and the
problem moves with the connection.

Once the link light goes out on the hub, I can, of course, no longer
contact the Linux box from a remote host.  However, I can get the Linux
network interface to "wake back up" by sending a ping packet from the
Linux box to some other host on the network.

Any ideas as to the problem might be?  I don't normally monitor this
mailing list so please reply directly to me at rschaaf@netway.com

Some more details about my configuration:

Linux kernel version: 2.2.5
Processor:            Pentium II, 400 MHz, 128 MBytes DRAM

Ethernet driver info (from the boot messages):
3c59x.c:v0.99H 11/17/98 Donald Becker                    
http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html
eth0: 3Com 3c905B Cyclone 100baseTx at 0xb000,  00:50:04:42:f1:64,
      IRQ 10
  8K byte-wide RAM 5:3 Rx:Tx split, autoselect/Autonegotiate
      interface.
  MII transceiver found at address 24, status 782d.
  Enabling bus-master transmits and whole-frame receives.

>From ifconfig:
eth0      Link encap:Ethernet  HWaddr 00:50:04:42:F1:64  
          inet addr:10.1.12.2  Bcast:10.1.15.255  Mask:255.255.252.0
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:4412 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4650 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100 
          Interrupt:10 Base address:0xb000

Thanks in advance for any advice.

Regards,
Rich Schaaf

======================================================================
Rich Schaaf                               Pingtel Corporation
Email: rschaaf@pingtel.com                Suite 2200
Voice: +1 (781) 938-5306                  400 West Cummings Park
Fax:   +1 (781) 938-9650                  Woburn, MA  01801
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