Lof (Ds1) - Cisco ONS 15327 User Documentation

Alarm Procedures
Always use the supplied ESD wristband when working with a powered ONS 15327. Plug the wristband
Caution
cable into the ESD jack located on the lower-right outside edge of the shelf assembly.
The procedure assumes that the BITS timing reference signal is functioning properly. It also assumes the
Note
alarm is not appearing during node turn-up.
Procedure: Clear the LOF Alarm
Verify that the line framing and line coding match between the BITS input and the XTC:
Step 1
a.
b.
c.
d.
e.
f.
g.
If the alarm does not clear when the line framing and line coding match between the BITS input and the
Step 2
XTC, replace the XTC card.
Note

14.4.68 LOF (DS1)

•
The LOF alarm indicates that the receiving ONS 15327 has lost frame delineation in the incoming data.
If the LOF appears on the XTC-14 card, the transmitting equipment may have its framing set to a format
that differs from the receiving ONS 15327.
Procedure: Clear the LOF Alarm on the XTC-14 Card
Verify that the line framing and line coding match between the XTC-14 port and the signal source:
Step 1
a.
Cisco ONS 15327 User Documentation, R3.3
14-50
In CTC node view or card view, note the slot and port reporting the alarm.
Find the coding and framing formats of the external BITS timing source. This should be in the user
documentation for the external BITS timing source or on the timing source itself.
Click the Provisioning > Timing tabs to display the General Timing window.
Verify that Coding matches the coding of the BITS timing source (either B8ZS or AMI).
If the coding does not match, click Coding to reveal a menu. Choose the appropriate coding.
Verify that Framing matches the framing of the BITS timing source (either ESF or SF [D4]).
If the framing does not match, click Framing to reveal the menu. Choose the appropriate framing.
Note On the timing tab, the B8ZS coding field is normally paired with ESF in the Framing field,
and the AMI coding field is normally paired with SF (D4) in the Framing field.
When you replace a card with an identical type of card, you do not need to make any changes to
the database.
Major, Service-Affecting
In CTC, note the slot and port reporting the alarm.
Chapter 14 Alarm Troubleshooting
June 2002