Installation and Reference Guide HP AdvanceStack 100Base-THub-12TX, Hub-12TXM, and Switch Modules 1997-06

Troubleshooting A-1
Appendix A: Troubleshooting
Diagnosing Hub Indicators
The AdvanceStack Hub-12TX/Hub-12TXM can be easily
monitored through its comprehensive panel indicators. These
indicators assist the network manager in identifying problems the
hub may encounter. This section describes common problems
you may encounter and possible solutions.
Symptom: Link indicator does not light up (green) after making a connection.
Cause: Network interface (e.g., a LAN adapter on the attached device),
network cable, or hub port is defective.
Solution: Check the power cord of both the hub and the attached device
and power source connections. If connections are secure then
try a different outlet, or try a different power cord to see if the
power cord is the problem. Be sure the network cable is plugged
into both the hub and corresponding device. Verify that the
proper cable type is used and its length does not exceed
specified limits (Chapter 2). Check the LAN adapter on the
attached device and cable connections for possible defects.
Replace the defective LAN adapter or cable if necessary. If the
problem persists, contact your HP-authorized reseller.
Symptom: Power indicator does not light up (green) after power on.
Cause: Defective power outlet, power cord, or internal power supply.
Solution: Check the power outlet by plugging in another device that is
functioning properly. Check the power cord with another
device. If these measures fail to resolve the problem, have the
unit’s power supply replaced by your authorized reseller.
Use the diagnostic procedures described in Chapter 2 and
Chapter 5 to verify that all other system components are