DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Architecture
1-25SPE Duplication
1
When shadowing into the standby SPE has been off (as when the system first
comes up), system software checks to see if it is safe to restore shadowing.
Handshake communication must be up. Then software verifies (with Test #920)
that the SPEs have identical hardware configurations. If this passes and there are
no shadow-relevant component failures, system software turns on shadowing
again.
Once shadowing is turned on, it is necessary to refresh the contents of standby
memory to bring it into full agreement with the active’s by copying every word of
active SPE memory to the standby. This takes approximately 5 minutes, though
traffic load can increase the duration. When completed, the standby SPE is said
to be "refreshed".
status spe
or the
Standby SPE Status Query Test (#855)
in the
STBY-SPE test sequence can be used to check the REFRESH status of the
standby. Unless the standby SPE is refreshed, interchange into it can disrupt
service for several minutes. Otherwise, interchanges are minimally disruptive. A
standby SPE exiting lock mode or just released from busyout must undergo this
full re-initialization.
System software tracks the operation and raises a major alarm when refresh
failure occurs. If shadowing stays on, system software automatically tries to
refresh again 5 minutes later.
Generally, memory shadowing should always remain on. But there are conditions
when the system legitimately operates with shadowing off:
■ The standby SPE is undergoing any restart.
■ The active SPE is undergoing a restart level of 2 or greater.
■ The active SPE is locked.
■ The standby SPE is busied out.
In any other situation, it is an error condition for shadowing to be off. The first 2
situations are transitory and shadowing should automatically be restored within
10 minutes. If shadowing has been on for several minutes, it is an error condition
for the standby not to be refreshed.
Initialization: Bringing the Standby SPE Up
When the standby SPE has been out of service or is first coming up, SPE
software executes the following steps:
1. Establishes handshake communication.
2. When SMM answers handshake, raises the standby SPE’s SOH to
not
refreshed
if it has no critical component alarms, or
partially functional
there are critical component alarms.
3. Tests for component mismatch (test number 920).
4. If there is no mismatch, and no major alarms against shadow-relevant
components, and if SMM permits, turns on memory shadowing
