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 proc edures. This can happen, for ex ample, when a slave

tone/clock circuit pack experi ences a l oss of signal and switches to receive

timing from the standby ATM-EI. In this case TDM-CLK 2305 error is logg ed,

and the clock p roblem should be ad dressed first, if p ossible.

To repair PNC components in a duplicated PNC proceed as follows:
1. Most repairs involve fixing a sing le 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 ac tive PNC, this also means that the
standby PNC is more severely faulted. Normally, the
standby
PNC is
repaired first, since it is the most sev erely impaired.
To repair the active PNC (standby is already repaired ), issue the set pnc
unlock command, which g enerates a spontaneous interchang e. In a PNC
demand interchang e with reset pnc interchange use the
override-and-lock qualifier for the active PNC. The

override-and-lock

option ensures that no subsequen t interchange can oc cur during the
repair of the standby PNC. A d emand interchange may n ot be necessary
if the following conditio ns drive a spontaneous interchan ge:
■The anti-thrashing period from the last interc hange 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 comp onent is on the standby PNC, and the PNCs
are locked in their current ac tive/standby state.
3. Busyout the PNC with the busyout pnc command.
4. Use fault isolation and comp onent testing proced ures for the individual
PNC components, just as for a simplex PNC. Replac ement of components
does disrupt op eration of the active PNC.
5. Once the failed comp onent is replaced, use the status pnc command to
check the health standb y PNC component.
6. When confident that the prob lem has been resolved, as ind icated 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 stand by 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 (cold 2) or 3 (cold1) do es not change
which PNC is active. If a PNC interchange was in p rogress when the reset
took place, the PNC interchange c ontinued until comp letion.