Avaya Definity SI, Maintenance Manual, Page: 771 / 2968

Packet Bus Fault Isolation Flowchart
Issue 4 May 2002 9-19 555-233-123
8. If the data matches the previously recorded data, a Packet Bus problem
exists. The original TN771 Maintenance/Test circuit pack is not defective,
and it does not need to be returned to the factory. Replace the original
TN771, then correct the Packet Bus problem by using the procedures in
the sections that follow.
9. If the data does not match the previously recorded data, the original TN771
Maintenance/Test circuit pack is defective. If there are still indications of
Packet Bus problems, correct them by using the procedures in the sections
that follow.
Packet Bus Fault Isolation Flowchart
The flowchart in this section presents the steps to be taken for isolating and
resolving Packet Bus problems. The order in which the maintenance objects
should be examined can be determined by assessing how wide-spread the failure
is. For example, since all ISDN-BRI devices communicate with the TN778 Packet
Control circuit pack, this MO should be examined early in the sequence. On the
other hand, a failure of a TN570 circuit pack in an EPN may cause ISDN-BRI
failure in an EPN, but it could not be the cause of a failure in the PPN.
Whenever the flowchart refers to the Maintenance documentation for a specific
MO, keep in mind that the repair procedure for that MO may in turn refer to
another MO’s repair procedure. The flowchart tries to coordinate these
procedures so that a logical flow is maintained if the Packet Bus problems are not
resolved via the first set of repair procedures. However, a Packet Bus failure can
lead to a somewhat haphazard referencing of various MO procedures that may
result in your implementing steps that either have already been completed or are
not necessary. If this occurs, return to the flowchart at the step that follows the
reference to
Chapter 10, ‘‘Maintenance Object Repair Procedures’’ , and then
continue.
NOTE:
The following status commands can also help diagnose Packet Bus
problems:
■
status system
■
status packet-control
■
status bri-port
■
status station
■
status data-module
For a description of these commands, refer to the “Status Commands”
section in
Chapter 8, ‘‘Maintenance Commands and Trouble-Clearing
Aids’’ . The commands provide information about the service state of
various Packet maintenance objects. This information can be useful for
remote maintenance, inasmuch it can explain the impact of the failure(s) on
the system.