DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-1581SYNC (Synchronization)
9
Synchronization Switches Away from the Current Timing Reference
Synchronization will switch away from a DS1 reference (primary or secondary) if
the current DS1 reference is not providing a valid timing signal. The other DS1
reference will be used if one is ad ministered and provid ing a valid timing signal.
Otherwise, the local oscillator of the Tone-Clock circ uit pack in the same p ort
network as the DS1 reference will be used. The following c onditions will cause a
synchronization switch:
■The current DS1 reference is not inserted (i.e. list configuration board
UUCSS shows "no board").
■The current DS1 reference has a loss of signal error (DS1-BD and
UDS1-BD error type 1281), a blue alarm error (DS1-BD and UDS1-BD
error type 1793), a red alarm error (DS1-BD and UDS1-BD error typ e
2049), or a hyperactive angel er ror (DS1-BD and UDS1-BD error type
1538). A corresponding alarm log entry is not required .
■DS1 and UDS1 circuit packs c an be administered wi th slips detection
enabled via the Slip Detection? field set to a y (see the add ds1, change
ds1, and display ds1 commands). When over half of the DS1 and UDS1
circuit packs ad ministered as slip enab led are experiencing slips, and the
primary or secondary synchronization reference is the current
synchronization reference, synchroniz ation will try the other administered
synchronization reference if the other adm inistered reference does not
have the above two conditions . The list measurements ds1-log
command can be used to get an historical perspec tive of DS1 facility
operation.
The following conditions will c ause a switch to the other DS1 reference if one
exists and the other DS1 reference is more healthy:
■The current DS1 reference has a misframe error (DS1-BD error type 3329
to 3345 or UDS1-BD error type 3585-3601). A correspond ing alarm log
entry is not required.
■The current DS1 reference has a slip alarm (DS1-BD and UDS1-BD error
type 3073 to 3160). A correspond ing alarm log entr y is required.
If the above conditions are rep aired and no longer ap ply, synchronization will
switch back to the p rimary reference.
Tone-Clock Circuit Pack LEDs
The yellow and green LEDs of the TN768 and TN780 Tone-Clock circuit pack s
flash in a specific p attern to indicate the status of the circuit pac k. For example,
these flashing LED patterns are used to ind icate if a Tone-Clock circuit pac k is
deriving timing from an external source or whether the Tone-Clock circuit pack is
providing the timing signal for the port network.