You can see that at least one other person had this problem as well:

My post:
http://lists.suse.com/archive/suse-linux-e/2005-Oct/3968.html
A response:
http://lists.suse.com/archive/suse-linux-e/2005-Oct/4011.html

Please provide the following information:
 - hwinfo --netcard
 - all /etc/sysconfig/network/ifcfg-* files
 - 'ps ax' and 'ip a' after reboot
 - 'ps ax' and 'ip a' after rcnetwork restart

hwinfo --netcard

  [Created at pci.277]
  UDI: /org/freedesktop/Hal/devices/pci_10b7_9200
  Unique ID: rBUF.oOfgbdRycVB
  Parent ID: 6NW+.Wc+DHj8LOy0
  SysFS ID: /devices/pci0000:00/0000:00:1e.0/0000:02:01.0
  SysFS BusID: 0000:02:01.0
  Hardware Class: network
  Model: "Dell 3c905C-TX/TX-M [Tornado]"
  Vendor: pci 0x10b7 "3Com Corporation"
  Device: pci 0x9200 "3c905C-TX/TX-M [Tornado]"
  SubVendor: pci 0x1028 "Dell"
  SubDevice: pci 0x00f3 
  Revision: 0x78
  Driver: "3c59x"
  Device File: eth0
  I/O Ports: 0x3000-0x3fff (rw)
  Memory Range: 0xe8000000-0xe800007f (rw,non-prefetchable)
  Memory Range: 0x1a000000-0x1a01ffff (ro,prefetchable,disabled)
  IRQ: 10 (1366 events)
  HW Address: 00:0b:db:15:95:c8
  Link detected: yes
  Module Alias: "pci:v000010B7d00009200sv00001028sd000000F3bc02sc00i00"
  Driver Info #0:
    Driver Status: 3c59x is active
    Driver Activation Cmd: "modprobe 3c59x"
  Config Status: cfg=no, avail=yes, need=no, active=unknown
  Attached to: #14 (PCI bridge)

'ip a' following a reboot shows that eth0 is unconfigured:

2: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop qlen 1000
    link/ether 00:0b:db:15:95:c8 brd ff:ff:ff:ff:ff:ff

'ip a' follwing a reboot and then an 'rcnetwork restart' shows eth0 configured properly:

2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:0b:db:15:95:c8 brd ff:ff:ff:ff:ff:ff
    inet 192.168.10.11/24 brd 192.168.10.255 scope global eth0
    inet6 fe80::20b:dbff:fe15:95c8/64 scope link 
       valid_lft forever preferred_lft forever

'ps ax' before and after 'rcnetwork restart' are identical except ifplug is now running (whereas before it was not). I did 'ps ax > a' and 'ps ax > b' (a is before and b is after) and diff'd a and b.

/sbin/ifplugd -i eth0 -r etc/sysconfig/network/scripts/ifplugd-selectif -f -I

hald is of course running (unchanged):
/usr/sbin/hald --daemon=yes --retain-privileges

Contents of /etc/sysconfig/network/ifcfg-eth-id-00:0b:db:15:95:c8
(I did not include ifcfg-lo)
***
BOOTPROTO='static'
BROADCAST=''
IFPLUGD_PRIORITY='20'
IPADDR='192.168.10.11'
MTU=''
NAME='Dell 3c905C-TX/TX-M [Tornado]'
NETMASK='255.255.255.0'
NETWORK=''
REMOTE_IPADDR=''
STARTMODE=ifplugd
UNIQUE='rBUF.oOfgbdRycVB'
USERCONTROL='no'
_nm_name='bus-pci-0000:02:01.0'
*****************************************

At least part of the problem appears to be in /sbin/ifup near line 308, which basically means that ifplugd won't get started if the 'mode' isn't hotplug.

ifup eth0 -o hotplug
/does/ start ifplugd.  Somehow,  ifup is not getting called at startup with -o hotplug.

Also, USE_SYSLOG="yes" doesn't appear to work.
I also tried when DEBUG="yes" but not all of the messages appear in /var/log/messages, and NONE of the debug messages do. I only see messages from:

ifplugd (after I called ifup eth0 -o hotplug)
ifup (No configuration found for tun0)
ifdown: Interface not available and no configuration found.
ifup-wireless: lo is not wireless, exiting

Is there anything else I can help with?  This is still an annoying problem for me.

A fresh install of another machine also has this problem.

*** This bug has been marked as a duplicate of 141554 ***