Nortel DMS-100 Series Maintenance Manual page 86

1-70 Maintenance overview
The audit discovers a mismatch in node status. A PM181 log with the
following reason must occur and OM PM2ERR must increment by one.
Node Status Mismatch
Call processing connection audit
The call processing connection audit maintains an order for the SMS and
RCS timeswitch connection records. The audit takes down connections
associated with connection release and connection setup messages. The
SMS sends the connection release and connection setup messages to the
RCS. The connection release and connection setup messages fail to receive
acknowledgments from the RCS.
IMC link audit
The system audits both IMC links in the SMS, one between the NT6X69
cards and one between the NT6X45 cards. The system audits the IMC links
to monitor the sanity of messages between the units. If the IMC audit fails
and the fault is detected at the node level, the node, both units of the SMS, is
placed in the ISTb state. If the fault is detected at the unit level, the fault
unit is placed in the ISTb state.
When the IMC link audit detects an IMC link failure, the following events
occur:
Refer to "Handling an IMC link fault" in the "Trouble isolation and
correction" section in this document for corrective action. When the fault is
fixed, the system audit opens the link again.
CMR card audit
An audit runs in-service diagnostics approximately every minute on the
CMR card. If an in-service fault is detected, the SMS is set to in-service
trouble (ISTb). A PM181 log is generated. The PM181 log indicates that
calling number delivery (CND) is not working for RCS lines connected to
the SMS. Operating company personnel can perform maintenance on the
defective CMR card as required after the system generates this log.
297-8231-550 Standard 09.01 August 1998
a fault is reported to the CM
the link is closed and SMS status changes to ISTb
the SMS processors no longer use link
a SWACT is prevented