DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Alarms, Errors, and Troubleshooting
5-79Packet Bus Fault Isolation and Repair
5
■‘‘Packet Bus Fault Isolation Flowchart’’ is the starting point for the
troubleshooting proces s. It is used to determine if a failure of ser vice is
caused by the p acket bus itself or b y another maintenance objec t on the
packet bus.
■‘‘Correcting Packet Bus Faults’’ presents the p rocedures required to
correct either a proble m with the packet bus itself or one tha t is caused by
a circuit pack connected to the Packet Bu s.
Remote Maintenance versus On-Site Maintenance
Most packet bus fault isol ation and repair proced ures require a technician to be
on-site. This is because a pac ket bus failures are caused b y a hardware failure of
either the packet bus itself o r a circuit pack that is connected to it. In itial
diagnoses can b e made via use of the Packet Bus Fault Isolation Flowchart, b ut
the Maintenance/Test Standalone Mode Procedure and the Packet Bus Fault
Correction Procedure require that a techni cian be on-site. These proced ures are
presented with this requirement in mind .
The flowchart refers to the repair proce dures in Chapter 9, ‘‘Maintenance Object
Repair Procedures’’ for various maintenance ob jects. When a decision p oint is
reached, a remotely located technician can refer to the ap propriate secti on and
attempt to resolve any fault cond itions. Some procedures require on-site rep air
action. Keep in mind that f ailure of a maintenance object a ppearing early in the
flowchart can cause a larms with maintenance objec ts that appear later in the
flowchart. Multiple d ispatches can b e prevented by remotely c hecking
subsequent stages on the flowchart and prep aring the on-site technic ian for
replacement of several co mponents if necessary.
The Maintenance/Test packet bus port described below provides status
information that is accessed with the status port-network P command an d the
PKT-BUS test sequence. The Maintenance/Test circuit pack may or may not b e
present at a customer site, dep ending on the c onfiguration of the switch. If a
Maintenance/Test circuit pack is not p resent, one must be taken to the site for
diagnosing packet bus problems.
In a sy stem w ith d upl icat ed SPEs, an SPE in terc hang e may r esolv e the p ac ket
bus problem. This operation c an be executed remo tely, and is discussed in

Packet Bus Fault Correction Procedures

below.