3Com 8 manual Problem Solving for the HUB 4 and 4C

PROBLEM SOLVING FOR THE HUB 4 AND 4C

The OfficeConnect hub has been designed to aid you when detecting and solving possible problems with your network. These problems are rarely serious, the cause is usually a disconnected or damaged cable, or incorrect configuration. If this section does not solve your problem, contact your supplier for information on what to do next.

Perform these actions first:

■Ensure all equipment is powered on.

■Power off the hubs, wait about 5 seconds and then power on the hubs.

Check the following symptoms and solutions:

Power LED not lit. Check your power adapter connection. If there is still no power, you may have a faulty power adapter which needs replacing with another OfficeConnect power adapter. Do not use any other power adapter

with the hub.

Alert LED continuously lit. There is either continual excessive use of your network (over 80%) or, more likely, a 10BASE-T port has partitioned due to a loop in your network (in which case the corresponding Port Status LED will be yellow). Examine your connections and remove the loop. Each piece of equipment needs only one connection to your OfficeConnect hub.

Port Status LED yellow for a 10BASE-T port. It is likely that there is a loop in your network which has caused this port to partition. Examine your connections and remove the loop. Each piece of equipment needs only one connection to your OfficeConnect hub. The LED will change from yellow to green, on receiving a valid packet on the port.

Link between two OfficeConnect hubs not working. Check your hub connections; follow the information given for your hub. With 10BASE-T it is likely an Uplink/Normal switch is incorrectly set. With 10BASE-2 it is likely a terminator (end piece) is not properly fitted; this would cause the Coax Port Status LED to light yellow (partition).

AUI/COAX Port Status LED not lit when external transceiver in use. Check the AUI cable is correctly connected to the hub and to the external transceiver. Ensure both slide locks are engaged.

AUI/COAX Port Status LED yellow when the 10BASE-2 port is not being used. The port has partitioned. This is correct operation.

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