Avaya MCC1 Maintenance Procedures page 238

Packet and serial bus maintenance
Isolating and repairing packet-bus faults
k Investigate errors and alarms in the following order:
1 Circuit-pack level
2 Ports
3 Endpoints
l Follow the
resolved with these procedures, follow normal escalation procedures.
Correcting packet-bus faults
Status port-network command
Status port-network P displays include the service state, alarm status, and (if the Maintenance/Test
packet-bus port is present) the number of faulty and open leads for the specified PN's packet bus. This
information can be used to determine the urgency of the repair. In general, a service state of "out"
indicates extreme urgency, while a service state of "reconfig" indicates moderate urgency.
NOTE:
Ultimately, the urgency of a repair is determined by the customer's requirements. A
customer who uses ISDN BRI for station sets, or who relies heavily on packet-bus
supported system-adjunct features (like DCS, AUDIX, or CDR) probably considers a
packet-bus fault critical. On the other hand, a customer with little ISDN-BRI service and
no adjunct features may consider even an uncorrectable packet-bus fault less important,
and may prefer to delay repairs due to their disruptive nature.
If background maintenance is running on the packet bus when the status port-network command is
issued, the data reported for the packet bus may be inconsistent due to updating by the tests. If the data
seem inconsistent, enter the command again.
If test results or the results of the status port-network command indicate that there are 24 faults on the
packet bus, the problem is probably caused by faulty cables between carriers, or by defective or missing
bus terminators. However, before proceeding, make sure that the Maintenance/Test packet-bus port is not
generating a false report by looking for an M/T-PKT error in the error log. Then test the Maintenance/Test
packet-bus port with test port UUCSSpp. If any problems are suspected, see
concerning the TN771D
NOTE:
If the carrier where a TN771D Maintenance/Test circuit pack is inserted does not have a -
5V power supply, the Maintenance/Test packet-bus port reports 24 open leads in response
to status port-network, or Test #572 of the PKT-BUS test sequence. See
(Carrier Power Supply)
238
Troubleshooting procedures
on page 234.
to ensure that a -5 Volt power supply is available.
on page 239. If the packet-bus problem cannot be
Special precaution
CARR-POW
Maintenance Procedures
December 2003