Can't ping the other computer over a "private" cable
 

Ok, so this is the story:

I have two computers connected to each other via a crappy router. The router itself is sufficient for sharing the Internet connection, but for filetransfers between the computers in the LAN, it's a bit slow, so I thought I might be able to speed things up a little by connecting my two computers to each other using a crossed-pair cable (or whatever they're called), bypassing the router.

The reason I didn't set up one of my two computers as a router instead of using the hardware router I'm using now, is that the two computers must be able to connect to the Internet at all times, even if one of them are down (which is about 50% of the time).

Anyway, so I threw in an extra NIC in each computer and configured them as I wanted things to be. I set Samba to bind only to the LAN-NIC (which I call the NIC connected to the other computer over the crossed-pair-cable), and disabled File & Printer Sharing on the Internet-NIC (connected to the router) on the other machine (running win2k, by the way).
I set up both LAN-NICs to use static IPs (192.168.0.2 and 192.168.0.3), and the LEDs on the LAN-NICs all light (which, by the way, they don't when connected usign a twisted-pair-cable so I know it's not a problem with that).
Linux detects both NICs, and Samba has no problems binding to the LAN-NIC. Same thing goes for Win2k.

Everything was set to go, I thought, but nooo.. The computers can't ping each other over the "private channel" (which I call the connection over the crossed-pair-cable), they do find each other via the router...

There's nothing wrong with the NICs or the cables; I tested both NICs on both computers (ie connected the Internet-NIC and then the LAN-NIC to the router), they both work.
Then I tried straightening the crossed-cable and connected the Internet-NIC to the router using that cable, and it works just fine.
As I mentioned above, all NICs work just fine, I can surf the Internet from either computer, using any NIC.

I'm not using any firewall on either computer, and I'm out of ideas. I've searched a bit on this forum, and seen others having similar problems, but I couldn't find one matching my problem 100%.

Computer 1: Slackware 10.0 running Linux 2.6.8.1
Computer 2: Win2k

Any ideas would be greatly appreciated.


Tomas412

Seems to me that your crossed cable isn't a crossed cable!

Are you pinging when you are checking the cable when it is connected to the router?

Did you try to ping from both machines?

It sounds like a physical problem rather than a configuration issue - but I might be wrong!

Hope this helps a little

F0ul Oli

It's a crossed cable for sure. I can connect the crossed one to the router, but that's only because it supports either twisted or crossed cables.
I got this little extender, it's crossed, so when I connect a crossed cable to it, the cable becomes a normal twisted pair and vice versa. Without the extender, all LEDs are lit on the NICs using the crossed cable. With the extender, they're off.
Using a twisted pair cable, without the extender the LEDs are off, and when using the twisted pair cable and the extender, the LEDs are on.


There must be something I've misconfigured in the software, I'm sure of it. Thanks for the tip, though.


Tomas412

What are the IP address range of the router NICs?

If they are also 192.168.0.x then change them to 192.168.1.x.

Of cource.... why didn't I think of that... Thanks alot! It works like a charm now!



Tomas412