DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Architecture
1-17SPE Duplication
1
Standby SPE Availability
The STBY-SPE maintenance object is responsible for testing of the standby SPE
so that any faults that would prevent it from being available for service can be
isolated and repaired. Various factors affect the availability of the standby SPE:
■ The condition of the individual hardware components of the standby SPE,
including circuit packs, power supplies, cables and other supporting
components.
Loss of power in an SPE due to power supply or power delivery
components is discussed under the condition SPE-Down. If a circuit pack
in the standby SPE that is critical to call service has failed, the standby will
not be able to become active. Maintenance testing of the standby SPE
allows isolation and repair of component problems so that the standby can
be made available again.
■ Standby memory content
Each write operation in active memory is shadowed to the corresponding
location in the standby SPE’s memory. The standby memory should be in
agreement with the active in order to support an interchange that will
preserve call, feature and translation information. Maintenance software
tracking the STBY-SPE MO aims to keep the two memories in agreement.
■ Standby State-of-Health (SOH)
The Duplication Interface circuit packs maintain a state-of-health value
which reflects the availability of the standby SPE. If the Standby SPE’s
state-of-health level is too poor, it cannot automatically be interchanged
into (made active).
■ Standby SPE-Down
If the standby SPE is completely dead and held reset by its SYSAM (in
SPE-Down), or the standby SPE has no power, it is unavailable for service.
■ System Time-of-Day
If the Time-of-Day clock of the standby SPE is substantially out of synch
with the active, interchanges could be more disruptive to service than
desirable.
System software running on both active and standby SPEs attempts to ensure
that the standby SPE is kept fully available in terms of the above factors. The
health of both the active and standby is tracked as a State-of-Health (SOH)
value.
