Alarms, Errors, and Troubleshooting
555-233-143
4-102
Issue 1 May 2002
Flowchart Notes
The following paragraphs refer by letter to corresponding entries in
. Individual errors and alarms are not detailed in this flowchart. When
referring to explanations of these in
Chapter 8, ‘‘Maintenance-Object Repair
, 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:
■
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?
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:
■
Assume that the answer to this question is “No.”
■
Check the IPSI’s Packet Interface circuit in this EPN.
d. A packet problem affecting more than one EPN is probably caused by
either an:
■
IPSI’s Packet Interface circuit fault
■
IPSI-connected EPN’s packet bus fault
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.
Summary of Contents for S8700 Series
Page 50: ...Maintenance Architecture 555 233 143 1 26 Issue 1 May 2002 ...
Page 74: ...Initialization and Recovery 555 233 143 3 12 Issue 1 May 2002 ...
Page 186: ...Alarms Errors and Troubleshooting 555 233 143 4 112 Issue 1 May 2002 ...
Page 232: ...Additional Maintenance Procedures 555 233 143 5 46 Issue 1 May 2002 ...
Page 635: ...status psa Issue 1 May 2002 7 379 555 233 143 status psa See status tti on page 7 406 ...
Page 722: ...Maintenance Commands 555 233 143 7 466 Issue 1 May 2002 ...