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Cisco ONS 15327 Troubleshooting Guide, R3.4
March 2004
Chapter2 Alarm Troubleshooting
Alarm Procedures
Step 5 If the secondary timing source is an incoming port on th e O NS 15327, complete the “Clear the LOS
(OC-N) Alarm” procedure on page 2-85.
Step 6 If the alarm does not clear, log onto http://www.cisco.com/tac for more information or call TAC
(1-800-553-2447).
2.6.180 SYNCTHIRD
•Minor (MN), Non-Service Affecting (NSA)
A Loss of Timing on Third Reference (SYNCTHIRD) alarm occurs when the ONS 15327 loses the third
timing source (reference 3). The ONS 15327 uses three ranking timing references. The timing references
are typically two BITS-level or line-level sources and an internal reference. If SYNCTHIRD occu rs and
the ONS 15327 uses an internal reference for source three, the XTC card might have failed. The
ONS 15327 often reports either a FRNGSYNC condition (see page 2-71) or a HLDOVRSYNC alarm
(see page 2-73) after a SYNCTHIRD alarm.
Caution Always use the supplied electrostatic discharge wristband when working with a powered ONS 15327.
Plug the wristband cable into the ESD jack located between the top high-speed and XTC slots.

Procedure: Clear the SYNCTHIRD Alarm

Step 1 In node view, click the Provisioning > Timing tabs.
Step 2 Verify the current configuration of the REF-3 for the NE Reference. For more inform ati on abou t
references, refer to the Cisco ONS 15327 Procedure Guide.
Step 3 If the third timing source is a BITS input, complete the “Clear the LOS (BITS) Alarm” procedure on
page 2-82.
Step 4 If the third timing source is an incoming port on the ONS15327, complete the “Clear the LOS ( OC -N )
Alarm” procedure on page 2-85.
Step 5 If the third timing source uses the internal ONS15327 timing, complete the “Reset the Active XTC Card
in CTC” procedure on page 2-129.
Verify that the active card you reset is now standby. The ACT/STBY LED of this card should be amb er,
and the newly active XTC card LED should be green.
Step 6 If the reset card has not rebooted successfully, or the alarm has not cleared, c all TAC (1-800-553-2447).
If the TAC technician tells you to reseat the card, complete “Remov e and Re in ser t (Res ea t) th e Stan dby
XTC” procedure on page 3-3. If the TAC technician tells you to remove the card and reinstall a new one,
follow the “Physically Replace a Card” procedure on page2-130.
Note When replacing a card with an identical type of card, no additional CTC provisioning is
required.