DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Object Repair Procedures
9-231ATM PNC-DUP (ATM PNC Duplication)
9
following repair procedures. This can happen, for example, when a slave
tone/clock circuit pack experiences a loss of signal and switches to receive
timing from the standby ATM-EI. In this case TDM-CLK 2305 error is logged,
and the clock problem should be addressed first, if possible.
To repair PNC components in a duplicated PNC proceed as follows:
1. Most repairs involve fixing a single fault on the standby PNC. Use
set pnc
lock
or
busy-out pnc
to prevent an interchange into the PNC being
repaired.
2. If a faulty component exists on the active PNC, this also means that the
standby PNC is more severely faulted. Normally, the
standby
PNC is
repaired first, since it is the most severely impaired.
To repair the active PNC (standby is already repaired), issue the
set pnc
unlock
command, which generates a spontaneous interchange. In a PNC
demand interchange with
reset pnc interchange
use the
override-and-lock
qualifier for the active PNC. The
override-and-lock
option ensures that no subsequent interchange can occur during the
repair of the standby PNC. A demand interchange may not be necessary
if the following conditions drive a spontaneous interchange:
■ The anti-thrashing period from the last interchange has expired.
■ The global refresh from releasing the standby PNC has completed.
■ The standby PNC State of Health is better than the active PNC.
At this point, the faulty component is on the standby PNC, and the PNCs
are locked in their current active/standby state.
3. Busyout the PNC with the
busyout pnc
command.
4. Use fault isolation and component testing procedures for the individual
PNC components, just as for a simplex PNC. Replacement of components
does disrupt operation of the active PNC.
5. Once the failed component is replaced, use the
status pnc
command to
check the health standby PNC component.
6. When confident that the problem has been resolved, as indicated by a
state of health with all zeros, unlock (
set pnc unlock
) and release
(release pnc) the PNC. Note that no further PNC interchange is required
since you can test the standby PNC as thoroughly as the active.
Interactions: SPE resets and PNC interchanges
■ After a reset system 4 (reboot), the A PNC is always the active.
■ A system reset of level 1 (warm), 2 (cold2) or 3 (cold1) does not change
which PNC is active. If a PNC interchange was in progress when the reset
took place, the PNC interchange continued until completion.
