LinuxQuestions.org - Internet connection sharing

Sorry for the long post - but here goes:

I have got an interesting problem with Windows XP SP2 and Knoppix 3.7 LiveCD (and also Gentoo 2004.3 Minimal LiveCD). I have a standard home phoneline network card which behaves in the same way as a normal ethernet card and therefore uses the "pcnet32" module. My gateway is an XP computer (pre-SP1) that runs Internet Connection Sharing so that I can crosswire the two computers and use ICS on mine.

In a nutshell - my problem is the following: I cannot configure my network card on the Gentoo LiveCD. In Windows XP - the card works perfectly well and I get no errors whatsoever. When I boot into the Knoppix 3.7 LiveCD - the ethernet card autoconfigures itself with no problems using DHCP (because ICS acts like a DNS server as well as a DHCP server). The real problem is when I boot into the Gentoo LiveCD - the card is detected fine, and can be configured using ifconfig - but I get carrier errors on the card as soon as I try to ping anything.

So, in Gentoo LiveCD - doing this:

ifconfig eth0 192.168.0.123 broadcast 192.168.0.255 netmask 255.255.255.0 up
route add default gw 192.168.0.1

And then changing /etc/resolv.conf to say this:

search mshome.net
gateway 192.168.0.1

Then I try to ping the gateway (192.168.0.1) and I get the following info when running ifconfig:

eth0 Link encap:Ethernet HWaddr ...
inet addr:192.168.0.123 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:19 dropped:0 overruns:0 carrier:19
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 KiB) TX bytes:4740 (4.6 KiB)
Interrupt:11 Base address:0x1040

I get carrier errors - but I have checked that the cable is plugged in and I know that the gateway is actually running...

I then reboot the computer and put the Knoppix CD in - "knoppix26 lang=us"
Knoppix configures itself and starts DHCP broadcasting with the internet working fine. This is what I get when I run ifconfig on a newly booted Knoppix 3.7 system:

root@ttyp0[knoppix]# ifconfig
eth0 Link encap:Ethernet HWaddr ...
inet addr:192.168.0.43 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::220:78ff:feb1:37c6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3915 (3.8 KiB) TX bytes:4740 (4.6 KiB)
Interrupt:11 Base address:0x1040

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:19 errors:0 dropped:0 overruns:0 frame:0
TX packets:19 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1449 (1.4 KiB) TX bytes:1449 (1.4 KiB)

No errors - and the internet is working fine. Now I am getting to the root of the problem: When I boot into windows and then re-boot (without a shutdown) into Knoppix - the autoconfiguration doesn't work and I get carrier error (the same as I did with Gentoo)...

A quick check (of when the internet is working in Knoppix) of my configation files:

root@ttyp0[knoppix]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.0.0 * 255.255.255.0 U 0 0 0 eth0
default 192.168.0.1 0.0.0.0 UG 0 0 0 eth0
root@ttyp0[knoppix]# cat /etc/resolv.conf
search mshome.net
nameserver 192.168.0.1

The routing is the same as in gentoo, the resolv.conf is the same as in gentoo - and the ifconfig is the same - except that I get carrier errors...

root@ttyp0[sysconfig]# cat netcard
FULLNAME="Advanced Micro Devices [AMD]|79c978 [HomePNA]"
DRIVER="pcnet32"

returns the same both in Knoppix and in Gentoo liveCD

I also thought that I should check if the pcnet32 module was loaded in the kernel (in both systems 2.6) - so I ran lsmod:

pcnet32 27876 0
mii 7936 1 pcnet32
crc32 8064 1 pcnet32

So, in effect, I can see no difference in my Knoppix and Gentoo configuration that could make carrier errors appear (I haven't touched the hardware). The interesting problem is that I cannot get Knoppix to run with network when I reboot straight from Windows. My guess is that Windows changes the NIC EEPROM settings when installing updates (as I have done) to incorrect ones - and when Linux attemps to use them you get TX carrier errors on the ethernet card.

Any suggestions as to what I could try to get my eth0 working in Gentoo? Or maybe Knoppix 3.7 bypasses the EEPROM settings and uses correct ones?