DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Object Repair Procedures
9-1567SYNC (Synchronization)
9
The
change synchronization
command is used to administer whether Stratum 3
or Stratum 4 synchronization is being used. The
change synchronization
command allows primary and secondary references to be administered for the
Stratum 4 option.
The
status synchronization
command shows the current synchronization
reference. The
display synchronization
command shows the synchronization
references (e.g. primary, secondary, stratum 3) that are administered.
The
list timing-source
command displays all DS1 and UDS1 locations that are
allowed to be administered as primary or secondary references with the
change
synchronization
command.
Other commands associated with Synchronization Maintenance are
disable
synchronization-switch
and
enable synchronization-switch.
These
commands are used to disable the ability of Synchronization Maintenance to
switch between synchronization references and to enable this switching ability,
respectively. The
set synchronization
command is executed only after
synchronization has been disabled and is used to manually switch to a specific
synchronization reference. This command is useful to diagnose synchronization
problems by forcing a specific reference (DS1, UDS1, or Tone-Clock) to be the
system synchronization reference to determine if a specific reference is providing
a valid timing signal. To switch synchronization to the Stratum 3 clock, use the
enable synchronization-switch
command after verifying that the Stratum 3
clock is wired correctly.
Approach to Troubleshooting
Slip errors are the primary symptom associated with being unsynchronized.
A correct Synchronization plan for the network keeps the systems within the
network transmitting data at approximately the same rate to avoid situations
where:
■ One system transmits data at a rate faster than another system can
receive the data (in which case data is lost).
■ One system transmits data at a rate slower than another system expects to
receive data (in which case data is repeated).
Either of these situations, data being lost or repeated, is a slip.
When troubleshooting synchronization problems when slips are the primary error
log entry indications of a synchronization problem, requires that the problem be
isolated to:
■ A problem outside of the switch, i.e., the switch is not properly
synchronized to the rest of the network.
■ A problem internal to the switch.
