DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Alarms, Errors, and Troubleshooting
5-99Packet Bus Fault Isolation and Repair
5
Object Repair 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. All alarms 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:
■ Are all packet bus alarms resolved?
■ Are all packet circuit pack port and endpoint alarms resolved?
■ Are all ISDN-BRI stations/data modules, ASAI adjuncts, System
Port supported adjuncts, Packet Gateway supported adjuncts, and
ISDN-PRI D-channel links in service?
■ Does the Maintenance/Test packet bus port (in normal or
standalone mode) still indicate a packet bus fault?
c. If only a single PN is affected, the Packet Interface is probably not the
source of the problem. Nonetheless, if all of the ISDN-BRI, Packet
Gateway, Packet Data, and Universal DS1 circuit packs are located in a
single EPN, assume that the answer to this question is ‘‘No,’’ and check
the Packet Interface.
d. A packet problem that affects more than one port network is probably
caused by either a Packet Interface failure or a PPN packet bus failure.
The Packet Interface is checked before the packet bus.
e. Because the packet bus in each port network is physically separate, each
affected port network must be checked individually. The PPN should be
checked first since any EPN packet problems are usually resolved once a
PPN packet problem is resolved. After resolving the problem in one port
network, make sure that problems in other port networks have also been
resolved.
f. This step applies only when attempting to resolve an EPN packet bus
problem. When checking the Expansion Interfaces in an EPN, be sure to
check the corresponding one(s) in the PPN. (G3r supports only the TN570
Expansion Interface, not the earlier TN776 Port Network Interface).
g. If a TN771D is not present, one must be installed to accommodate the
standalone mode. See the above section on standalone mode.
h. 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.
i. If work is being done on-site, follow the procedures described earlier in
this discussion on standalone mode. If work is not being done on-site, go
to the next step.
