User`s guide

7-10

Diagnostics and Troubleshooting

• Check for loose port connections. Check all connectors to the

modules (especially twisted pair connectors, which may be

fragile).

• Check to make sure all the modules are ﬁrmly connected; check

all the screws are fully tightened.

• Number of carrier losses is increasing. This indicates that the

transceiver is not present or the transceiver's 10BASE-T

connection is suspect. Check the transceivers to ensure they are

ﬁrmly connected.

• Number of total collisions has dramatically increased. Check the

BNC transceiver, it may be lacking a terminator or its BNC

connector may be touching another transceiver's BNC

connector. Packets that are not being bridged/routed correctly

can also cause total collisions to increase. Verify the aging time

and the IP addresses of the ATX.

• Make sure UTP Transceivers are not pre-10BASE-T.

• DEC Broadband AUI Transceiver is not supported by the ATX.

• Unix spray command loses packets if workstations are busy.

• RESET button is depressed in an effort to reset the module. The

RESET button merely takes the module ofﬂine. To reset the

module or to bring it online use LCM. (On newer modules the

button is labelled OFFLINE, rather than RESET.)

7.5.4 ATX Has Rebooted

• Check the NMS configFatalErr trap to determine the reason

for the reboot.

7.5.5 ATX Does Not Respond To NMS

• Check status of ports using LCM.

• See if Spanning Tree topology is stable on LCM.