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Packard IE5.01 SP1)

Description of problem:
network operates correctly with 3 but not with 4 tulip NICs;
operates correctly with 2 each tulips and 2 each 8139 NICs.
Routing broken with 4 tulips--eth0, eth1, eth2 cannot get
out on the wire, eth3 still can.  (All NICs Fast Etherent.)

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. mobo Supermicro P6DGU, two Coppermine@550MHz, 512M Ram, 4 each
   genuine Kingston 100BASE-T tulips connected each to own switch,
   full duplex. (there is an adaptec 1542 also on the ISA bus).
   NOTE: machine dual-boots W2K server.
2. Each NIC serves its private lan 192.168.(1|2|3|4).0 at
   IP 192.168.(1|2|3|4).10 trivially routed, no IP forwarding.
   Routing tables identical btw. rh7.1 and W2K, works ok for W2K.
   No errors in /proc/net/dev, ifconfig OK, netstat -r OK,
   dmseg shows cards installed and sharing PCI interrupts,
   /etc/modules.conf checks fine.
3. Ping 192.168.4.50 (another machine known to be working) succeeds.
   Ping 192.168.(1|2|3).whatever does not (Host (i.e. not network)
   Unreachable).  telnet fails with host unreachable for nets (1|2|3).0
   (works fine with W2K).
4. Unplug eth3 (remove from PCI bus) --> eth0, eth1, eth2 now work.
5. Unplug eth2, replace eth2 with D-link 8139, replace eth3 with
   D-link 8139 also, reconfigure as needed --> all four cards now
   work as expected. 

Actual Results:
* kernel rh 7.1 uniproc out of the box, as described.
* kernel rh 7.1 smp out of the box, as described.

Expected Results:
setup with 4 tulips works fine with W2K so it's not a hardware
problem.  Should have worked with rh 7.1 too.

Additional info: