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 exp licitly to the TDM bus
(except TDM-CLK) should b e considered a po ssible cause of pac ket bus
problems.
a. Problems with the system clock (TDM-CLK) can c ause service disrup tions
on the packet bus. All alarms active against TDM-CLK should be resolved
first, even if the explanation refers only to TDM bus. A p acket bus p roblem
cannot cause a TDM-CLK problem, b ut a TDM-CLK problem can cause a
packet bus prob lem.
b. Throughout the flowchart, the question, ‘‘Are the p acket bus prob lems
resolved?,’’ refers to the problems that led you to t his chart, and can
involve several checks, such as:
■Are all packet bus alarms resolved?
■Are all packet circ uit pack port and endpoint alarms resolved ?
■Are all ISDN-BRI stations/data modules, ASAI adjuncts, System
Port supported adj uncts, Packet Gateway suppor ted adjuncts, and
ISDN-PRI D-channel links in service?
■Does the Maintenance/Test packet bus port (in normal or
standalone mode) still ind icate a packet b us fault?
c. If only a single PN is affected, the Packet Interface is prob ably not the
source of the problem. Nonetheless, if all of the ISDN-BRI, Packet
Gateway, Packet Data, and Universal DS1 circuit packs are loc ated in a
single EPN, assume that the answer to this question is ‘‘No,’’ and c heck
the Packet Interface.
d. A packet prob lem that affects more than one port ne twork is probably
caused by either a Packet In terface failure or a PPN packet bus failure.
The Packet Interface is checked before the packet b us.
e. Because the packet b us in each port network is physically sepa rate, each
affected port network must b e 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 p ort
network, make sure that problems in other p ort networks have also been
resolved.
f. This step applies only when attemp ting to resolve an EPN packet bus
problem. When checking the Expansion Interfaces in an EPN, be sure to
check the corresp onding one(s) in the PPN. (G3r supports only the TN570
Expansion Interface, not the earlier TN776 Port Network Interfac e).
g. If a TN771D is not present, one must be installed to accommodate the
standalone mode. See the above sec tion on standalone mode.
h. If a TN771D is present, it can fail in such a way that it eventually disrupts
the packet bus or misi nterprets a packet b us problem.
i. If work is being done on-site, follow the procedures de scribed earlier in
this discussion on standalone mod e. If work is not being done on-site, g o
to the next step.