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Description of problem:
We have a case with a HP Proliant DL 380 G3 (which seems to be noted
as supported by RHEL 3,
http://hardware.redhat.com/hcl/?pagename=details&hid=5257 ). This
machine has two onboard Tigon gigabit ethernet controllers. They seem
to work well with the tg3 driver. When patching one of these with a
switch with hard settings (eg no autonegotiation) 100MBit Full Duplex,
we get problems, as the driver (probably?) will probe for working
modes, and stop at 100MBit Half Duplex, where it detects a working link.

To get Full Duplex, one has to use a tool to force the correct values.
We tried both mii-tool and ethtool. The latter is known to work with
the same machine with earlier RedHat kernels.

Now, we Run ES 3 with the standard installed kernel (tried both up and
smp). With this kernel, running netconf has no impact on the availble
settings at least not the ones we use (speed, autonegotiation, duplex)


Version-Release number of selected component (if applicable):
kernel-2.4.21-4.EL

How reproducible:
Always

Steps to Reproduce:
1. Connect your HP Proliant DL380 G3 Tigon gigabit ethernet port to a
fixed 100MBit Full Duplex switch without autonegotiation
2. Boot up Linux. Take up a network interface
3. Use dmesg or ethtool to look at the duplex mode (half duplex)
reported by the driver. 
4. Try to use netconf to change autonegotiation and duplex mode,
something like this:

ethtool -s eth0 autoneg off
ethtool -s eth0 speed 100
ethtool -s eth0 duplex full
  

Actual Results:  Link stays in 100MBit Half Duplex mode


Expected Results:  Link changes to 100MBit Full Duplex mode


Additional info:

Workaround: Boot with a custom kernel. With a self-built kernel.org
kernel, ethtool works as expected. The RedHat Linux 9 kernels also work.