Avaya S8700 Maintenance Manual page 176

Alarms, Errors, and Troubleshooting
Flowchart Notes
The following paragraphs refer by letter to corresponding entries in
page 4-101. Individual errors and alarms are not detailed in this flowchart. When
referring to explanations of these in
Procedures'', any that do not refer explicitly to the TDM bus (except TDM-CLK)
should be considered a possible cause of packet-bus problems.
a. Problems with the system clock (TDM-CLK) can cause service disruptions
on the packet bus. Every alarm active against TDM-CLK should be
resolved first, even if the explanation refers only to TDM bus. A packet-bus
problem cannot cause a TDM-CLK problem, but a TDM-CLK problem can
cause a packet-bus problem.
b. Throughout the flowchart, the question, "Are the packet-bus problems
resolved?," refers to the problems that led you to this chart, and can involve
several checks, such as:
c. If only one EPN is affected, its Packet Interface circuit is probably not
causing the problem. Nonetheless, if every ISDN-BRI and Universal DS1
circuit pack resides in the same EPN:
d. A packet problem affecting more than one EPN is probably caused by
either an:
Check the IPSI's Packet Interface circuit before checking the packet bus.
e. Because each EPN's packet bus is physically separate, each affected EPN
must be checked individually. (However, IPSI-connected EPNs should be
checked first. Once an IPSI-connected EPN's packet problem is resolved,
any problems within it's scope are also usually resolved.) After resolving
the problem in one EPN, verify that problems are also resolved in any other
affected EPNs.
f. If a TN771D is absent, one must be installed to accommodate the
stand-alone mode. See the previous section on stand-alone mode.
g. If a TN771D is present, it can fail in such a way that it eventually disrupts
the packet bus or misinterprets a packet-bus problem.
4-102 Issue 1 May 2002
Chapter 8, ''Maintenance-Object Repair
Is every packet-bus alarms resolved?
Is every packet circuit pack's port and endpoint alarm resolved?
Is every ISDN-BRI station/data module, ASAI adjunct, system port
supported adjunct, and ISDN-PRI D-channel link in service?
Does the Maintenance/Test packet-bus port (in normal or
stand-alone mode) still indicate a packet-bus fault?
Assume that the answer to this question is "No."
Check the IPSI's Packet Interface circuit in this EPN.
IPSI's Packet Interface circuit fault
IPSI-connected EPN's packet bus fault
Figure 4-46 on
555-233-143