36 Hardware Maintenance Manual: xSeries 250
Network connection problems
If the Ethernet controller cannot connect to the network, check the following:
• Make sure that the cable is installed correctly.
The network cable must be securely attached at all connections. If the cable is
attached but the problem persists, try a different cable.
If you set the Ethernet controller to operate at 100 Mbps, you must use Category 5
cabling.
If you directly connect two workstations (without a hub), or if you are not using a
hub with X ports, use a crossover cable.
Note: To determine whether a hub has an X port, check the port label. If the label
contains an X, the hub has an X port.
• Determine if the hub supports auto-negotiation. If not, try configuring the
integrated Ethernet controller manually to match the speed and duplex mode of
the hub.
• Check the Ethernet controller lights on the operator information panel.
These lights indicate whether a problem exists with the connector, cable, or hub.
— The Ethernet Link Status light illuminates when the Ethernet controller
receives a LINK pulse from the hub. If the light is off, there might be a
defective connector or cable, or a problem with the hub.
— The Ethernet Transmit/Receive Activity light illuminates when the Ethernet
controller sends or receives data over the Ethernet Network. If the Ethernet
Transmit/Receive Activity light is off, make sure that the hub and network
are operating and that the correct device drivers are loaded.
— The Ethernet Speed 100 Mbps light illuminates when the Ethernet controller
LAN speed is 100 Mbps.
• Make sure that you are using the correct device drivers, supplied with the server.
• Check for operating system-specific causes for the problem.
• Make sure that the device drivers on the client and server are using the same
protocol.
• Test the Ethernet controller.
How you test the Ethernet controller depends on which operating system you are
using (see the Ethernet controller device driver README file).
Ethernet controller troubleshooting chart
You can use the following troubleshooting chart to find solutions to 10/100 Mbps
Ethernet controller problems that have definite symptoms.