Still can't connect to LAN

[Harry Kuhman]

Can't ping from Win98SE or WinXPSP2 to Linux, don't see router.

don't see router from Knoppix, or don't even see router from Windows? Either way it makes no sense, but it will help to be very precise here if we are going to spot what is wrong and not make assumptions.

It's time to post all details. Local IP addresses (there is no reason to keep these hidden as they can't be reached by the Interner anyway). Post the output of ifconfig on Knoppix and ipconfig on the Windows boxes. We need IP addresses as well as masks and the rest. And post the model of that Linksys router, and anything else that you can think of that may help. Look over all of the web setup information in the router for clues.

Firewall for XP is off

You're sure for the XP system that you are not also running the damn Windows firewall, that is turned on by default in SP2? Boy, this sure looks like a firewall issue. Can't be a MAC filter issue in the router or you couldn't get to the Internet.

I have tried unplugging cable modem,

That one doesn't make much sense to me, since all systems were getting to the Internet just fine. It has to be more local.

still can't see each other on the LAN. Nothing will showup in My Network Places or LinNeighbborhood.

I'm not concerned about getting networking working yet. There are some issues that it works differently between XP and 98, having both on your system you may need to make a few setting just right to get everyone on the same page. But you are not going to get networking going if you can't even ping, so I would focus on that first.

You are trying to ping the windows boxes (and the knoppix box from windows) by IP address and not by name, are you not? As in ping 192.168.0.100 ? Are you 100% certain that you are using the correct IP addresses?

One thing that you may have to resort to is to watch the low level packet trafic as you try to ping the systems. Knoppix has Ethereal which is great for this purpose. I suspect if you watch an attempted ping from Knoppix you will see the ping packet go out but just never see a response (if you don't see the ping go out then that tells us something is wrong). But I suspect that if you watch the NIC (eth0) with ethereal and then ping the Knoppix system from windows you will see the ping (ICMP) packet come in and the response packet go back out. It would be worth examining the addresses closely in those packets but I still want to think that it will be a Windows firewall issue (although 98 has no default firewall, weakening that theory).