Avaya S8700 Maintenance Manual page 1713

ISDN-TRK (DS1 ISDN Trunk)
Alarming Based on Service States
A warning alarm is logged against a DS1 ISDN B-channel trunk when it is placed
in the Maintenance/Far-End or Out-Of-Service/Far-End states, during which the
trunk is unusable for outgoing calls. When a warning alarm is present, use status
trunk group#/member# command to determine the exact state. Other alarms
can be diagnosed by using the short and/or long test sequences. Note that an
ISDN B-channel trunk can be placed in a Far-End service state by either action
taken by the far-end switch or by failure of the far-end switch to respond. For
example, if the far end does not respond to a Remote Layer 3 Query test (#637)
for ISDN-SGR, the associated DS1 ISDN trunk B channels will be placed in the
Maintenance/Far-End service state.
As a port on a DS1 circuit pack (DS1-BD or UDS1-BD), and as part of a signaling
group dependent on a D channel (ISDN-LNK) for signaling, operation of the
ISDN-TRK is dependent on the health of these other MOs. In turn, the ISDN D
channel depends on the packet bus (PKT-BUS) for transmission through the
system. Keep this hierarchy of dependencies in mind when diagnosing problems.
DS1 ISDN Trunk Service States
The status trunk command displays the following possible service states for
ISDN trunks.
each state.
In-Service (INS)
The B channel is in its normal operating state.
Out-of-Service/Far-End (OOS/FE)
A B channel is initialized to this state when administered. The switch
sends messages to the far end to negotiate the B channel into service. If
the far end does not respond to the messages within a certain time period,
then the service state remains out of service and maintenance will
periodically resend the messages. The trunk is unusable for incoming and
outgoing calls.
Out-of-Service/Near-End (OOS/NE)
This is the state of the trunk when the NPE Crosstalk Test fails or when the
trunk is busied out by system technician. In this state, the trunk is unusable
for incoming or outgoing calls. No messages are sent to the far end until
the signaling link comes back into service or the trunk is released by
system technician.
555-233-143
Table 8-391 on page 8-993 gives recommended procedures for
Issue 1 May 2002 8-991