Chapter 22-202.4 Troubleshooting the Network2.4.1 Overview0008-8563Perform this procedure only when connecting the machine to networks.If the machine fails to be connected to networks, any of the following causes is probable.a. Connection failure between networks and the machineb. TCP/IP setting failure of the machinec. User network failured. Main controller PCB failureThe detailed check methods are as follows.2.4.2 Checking with Loopback Address0008-8564The loopback address returns before the network controller. Therefore, you can check whether TCP/IP settings of the machine are appropriate by executingPing with this address.1) Enter the loopback address (127.0.0.1) in PING.- If NG is displayed, check TCP/IP settings of the machine again, and re-execute Ping.- If OK is displayed, perform the next check.2.4.3 Checking with Local Host Address0008-8565The local host address is the IP address of the machine. Since the local host address returns in response to the network controller by executing Ping withthe address, you can check whether the network controller (main controller PCB) is in a normal condition.1) Enter the IP address of the machine in PING.If NG is displayed, take the following actions, and re-execute Ping.- IP address error of the machine: Check to see again if the IP address settings of the machine are appropriate. Ask the system administrator whether theallocated IP address is valid.- Failure in the main controller PCB: Replace the main controller PCBIf OK is displayed, a cause may be user's network environment. Inform the system administrator of the current situation, and ask for measures.
