Failed pinging a LAN card of the server from the client using shared internet connection

The server (Windows XP Pro SP3) has two LAN cards (LAN card A and B) and is connected to the internet using ADSL. The ADSL connection is shared to LAN card B using Internet Connection Sharing.

The client (Windows XP Pro SP3) has one LAN card, and is connected to LAN card B of the server so that it has access to the internet.

The IP address on the LAN cards are defined as follows:

Server:
 LAN card A: 192.168.0.3/24 (manually defined by me)
 LAN card B: 192.168.0.1/24 (manually defined by Internet Connection Sharing)

Client:
 LAN card: 192.168.0.123/24 (assigned by DHCP) Default gateway: 192.168.0.1

From the server, I can ping 192.168.0.123 successfully.

From the client, it can access the internet without any problem. I can also ping 192.168.0.1 successfully but for 192.168.0.3, it failed with the Request Timeout error message.

Why did the ping fail, and what should be done to make the ping possible? (all firewalls have been turned off.)

From serverfault bobo

• To start with, you should not have two identical subnets on multiple disjointed networks. The reason is that the Windows sees that both cards have access to the entire 192.168.0.x network - when in fact, they don't.

  What will be happening is that when you ping 192.168.0.3 from the client machine, the machine will be sending the ping response back on LAN A interface, rather than the LAN B interface (because it doesn't know any better).

  You will need to ensure that one of your networks is different. You should have, say 192.168.0.x and 192.168.1.x (both with a subnet mask of 255.255.255.0) for this to be a correct network setup.

  bobo : Yes, you are right. Following your solution, the ping works now!
  From Farseeker