Try the following procedures:v Make sure that the correct device drivers, which come with the server areinstalled and that they are at the latest level.v Make sure that the Ethernet cable is installed correctly.– The cable must be securely attached at all connections. If the cable isattached but the problem remains, try a different cable.– If the Ethernet controller is set to operate at 100 Mbps, you must useCategory 5 cabling.– If you directly connect two servers (without a hub), or if you are not using ahub with X ports, use a crossover cable. To determine whether a hub has anX port, check the port label. If the label contains an X, the hub has an X port.v Determine whether the hub supports auto-negotiation. If it does not, tryconfiguring the integrated Ethernet controller manually to match the speed andduplex mode of the hub.v Check the Ethernet controller LEDs on the rear panel of the server. These LEDsindicate whether there is a problem with the connector, cable, or hub.– The Ethernet link status LED is lit when the Ethernet controller receives a linkpulse from the hub. If the LED is off, there might be a defective connector orcable or a problem with the hub.– The Ethernet transmit/receive activity LED is lit when the Ethernet controllersends or receives data over the Ethernet network. If the Ethernettransmit/receive activity light is off, make sure that the hub and network areoperating and that the correct device drivers are installed.v Check the LAN activity LED on the rear of the server. The LAN activity LED is litwhen data is active on the Ethernet network. If the LAN activity LED is off, makesure that the hub and network are operating and that the correct device driversare installed.v Check for operating-system-specific causes of the problem.v Make sure that the device drivers on the client and server are using the sameprotocol.If the Ethernet controller still cannot connect to the network but the hardwareappears to be working, the network administrator must investigate other possiblecauses of the error.56 IBM System x3250 Types 4364 and 4365: Problem Determination and Service Guide