Avaya Definity SI Maintenance Manual page 1550

Maintenance Object Repair Procedures
d. This is the normal state for an Active Expansion Interface circuit pack that
is not the bus master. It is also the state of the TN776 Expansion Interface
circuit pack immediately after circuit pack initialization when the system has
not yet assigned a role to it (that is, Active or Standby). To distinguish
between these two situations, use the status system command. If the link
which contains this Expansion Interface circuit pack is in-service (up), the
Expansion Interface circuit pack is active; if it is out-of-service (down), the
Expansion Interface circuit pack is neither active nor standby.
e. This is the normal state for a Standby Expansion Interface circuit pack. It is
also the state of the TN570 Expansion Interface circuit pack immediately
after circuit pack initialization when the system has not yet assigned a role
to it (that is, Active or Standby). To distinguish between these two
situations, use the status system command. If the link which contains this
Expansion Interface circuit pack is in-service (up), the Expansion Interface
circuit pack is standby; if it is out-of-service (down), the Expansion
Interface circuit pack is neither active nor standby.
When testing Expansion Interface circuit packs to investigate problems, tests
should always be run on both circuit packs of an Expansion Link. This provides a
better indication of where a problem is located. Hardware errors for all Expansion
Interface circuit packs (EXP-INTF) may be displayed by using the category "infc"
on the Display Errors form.
In the EPN, the EPN TN775 Maintenance (MAINT) circuit pack monitors the
sanity of the Expansion Interface circuit pack. If the Expansion Interface circuit
pack should cycle between sane and insane several times, the Maintenance
circuit pack holds the Expansion Interface circuit pack reset. If a new Expansion
Interface circuit pack is installed in the EPN, the EPN Maintenance circuit pack
should be removed because it may attempt to hold the new Expansion Interface
circuit pack reset. The Maintenance circuit pack may be reinstalled after the
Expansion Interface circuit pack has been inserted and the Expansion Interface
circuit pack's red LED has gone off.
The Active Expansion Link is also involved in synchronization between the two
cabinets. The Expansion Interface circuit pack reports slip errors if the two
cabinets are not correctly synchronized. When diagnosing synchronization
problems, the Expansion Interface circuit packs should be examined as a possible
cause.
10-764 Issue 4 May 2002 555-233-123