14-56
Cisco ONS 15327 User Documentation, R3.3
June 2002
Chapter 14 Alarm Troubleshooting
Alarm Procedures
Step 6
Perform a soft reset on the far-end card.
Step 7
Switch from the far-end working card to the far-end protect card.
14.4.75 LOS (BITS)
•
Major, Service-Affecting
The XTC card has a loss of signal (LOS) from the BITS timing source. An LOS alarm occurs when a
SONET receiver detects an all-zero pattern for 10 microseconds or longer. An LOS (BITS-N) means the
BITS clock or the connection to the BITS clock failed.
Caution
Always use the supplied ESD wristband when working with a powered ONS 15327. Plug the wristband
cable into the ESD jack located on the lower-right outside edge of the shelf assembly.
Procedure: Clear the LOS Alarm
Step 1
Verify the wiring connection from the ONS 15327 backplane BITS clock pin fields to the timing source.
Step 2
Check that the BITS clock is operating properly.
14.4.76 LOS (DS-N)
•
Critical, Service-Affecting
The LOS is alarm indicates a loss of signal at the card for an XTC card port. LOS occurs when the port
on the card is in service but no signal is being received. The cabling is not correctly connected to the
card, or no signal exists on the line. Possible causes for no signal on the line include upstream equipment
failure or a fiber cut.
Caution
Always use the supplied ESD wristband when working with a powered ONS 15327. Plug the wristband
cable into the ESD jack located on the lower-right outside edge of the shelf assembly.
Procedure: Clear the LOS Alarm on the XTC Card
Step 1
Verify cabling continuity to the port.
Step 2
Verify that the correct port is in service.
Step 3
Use a test set to confirm that a valid signal exists on the line. Test the line as close to the receiving card
as possible.
Step 4
Ensure that the transmit and receive outputs from the DSx panel to your equipment are properly
connected.
Step 5
If there is a valid signal, replace the DS-N connector on the ONS 15327.
Summary of Contents for ONS 15327
Page 22: ...Contents xxii Cisco ONS 15327 User Documentation June 2002 I N D E X ...
Page 30: ...Figures xxviii Cisco ONS 15327 User Documentation June 2002 ...
Page 44: ...Procedures xlii Cisco ONS 15454 Installation and Operations Guide R3 2 June 2002 ...
Page 540: ...Glossary GL 16 Cisco ONS 15327 User Documentation R3 3 June 2002 ...