Filter
Top Products
DEFINITY ECS Release 8.2 Maintenance for R8.2csi
555-233-119 Issue 1
April 2000
Maintenance Objects
3-203ATM PNC-DUP (ATM PNC Duplication)
3
Refresh and unrefresh of the standby PNC
In a fully-functional PNC with healthy standby and active sides, the standby PNC
has a complete set of call connections corresponding to those in the active PNC.
If, however, the state of health of the standby PNC degrades, a selective
unrefresh of those connections that utilize the faulted component(s) is performed.
If the health of the standby PNC improves, a selective refresh of connections on
the affected route is performed so that call setup is consistent between the active
PNC and the healthy parts of the standby PNC.
The
Standby Refreshed?
field on the
status pnc
screen does
not
refer to the
selective type of refresh. It refers only to a global refresh that is performed when:
■ The system is initialized and PNC duplication is enabled.
■ There has been a spontaneous PNC interchange.
■ The standby PNC has been released from busy-out.
■ A system reset of level 2 or higher has taken place.
The refreshed field may display yes when in fact the standby is partially
unrefreshed. An interchange into an incompletely refreshed standby results in
dropped calls. This can happen when a more severe fault occurs on the active
PNC or when
reset pnc interchange
is used with the override option.
PNC interchanges
PNC spontaneous interchanges occur when PNC duplication software
determines that the State of Health (SOH) of the standby PNC is better than that
of the active PNC.
■ PNC-DUP executes a spontaneous interchange in response to a message
from a PNC component maintenance object indicating that either a fault
has occurred on the active PNC or a fault has been resolved on the
standby PNC.
■ The PNC SOH is compared to the standby PNC, and an interchange
occurs if the state of health of the standby PNC is now better than that of
the active PNC.
■ A corresponding Major or Minor alarm is logged by the reporting MO,
stimulating an alarm report.
When the resolution of a fault on the standby renders it more healthy than a
simultaneously-faulted active PNC, the error message indicates the type and
location of the
improved
component.