DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Architecture
1-26Power Interruptions
1
5. If memory shadowing is successfully turned on, initiates the process of
overall memory refresh
6. When refresh completes, if there are no critical component major alarms,
raises the standby SPE’s SOH to level
functional
Standby SPE initialization is a lower priority than initializing the active SPE and is
therefore “paced” to lower CPU consumption. The above steps are carried out at
10 second intervals. During system initialization, the above sequence begins
about 2 minutes after the terminal login prompt becomes available. Normally, the
standby SPE should be fully initialized about 5 minutes after the availability of the
login prompt. You can follow the execution of this sequence by repeatedly
entering the command “status spe.”
Should a step of this initialization sequence fail, system software retries that step
at 30 second intervals until it succeeds. It does not proceed to the next step until
the current one has succeeded. The failed condition is alarmed.
A procedure for bringing up the standby SPE after being in the SPE-down or
locked modes is described at the end of Chapter 4, ‘‘Initialization and Recovery’’
.
Power Interruptions
System cabinets and their associated power supplies can be powered by
110/208 volts AC either directly or from an Uninterruptible Power Supply (UPS)
system. Alternatively, the cabinets and their power supplies may be powered by
a -48 VDC battery power plant, which requires DC-to-DC conversion power units
in the system.
If power is interrupted to a DC-powered cabinet or an AC-powered cabinet
without optional backup batteries, the effect depends upon the decay time of the
power distribution unit. If the interruption period is shorter than the decay time,
there is no effect on service, though some -48V circuits may experience some
impact. If the decay time is exceeded for a PPN, all service is dropped,
emergency transfer is invoked and the system must reboot when power is
restored. If the decay time is exceeded for an EPN, all service to that Port
network is dropped and the EPN must be reset when power is restored. If the
EPN contains a Switch Node carrier, all service to Port Networks connected to
that Switch Node is dropped.
Single-carrier cabinets, which can be used for EPNs, also have no battery
backup. If power is interrupted for more than 0.25 seconds, all service is
dropped, and emergency transfer is invoked for the EPN.
In the above cases, the cabinet losing power is unable to log any alarms.
However, in the case of an EPN going down while the PPN remains up, alarms
associated with the EPN will be reported by the system.
