14-59
Cisco ONS 15327 User Documentation, R3.3
June 2002
Chapter 14 Alarm Troubleshooting
Alarm Procedures
A loopback facility (LPBKFACILITY) alarm means a software facility loopback is active for a port on
the reporting card. Loopback is a commonly used troubleshooting technique. A signal is sent out on a
link or part of the network and returned to the sending device. By setting up loopbacks on various parts
of the network and excluding other parts, a troubleshooter can logically narrow down the source of the
problem. For more information on loopbacks, see
“Network Tests” section on page 12-19
.
There are two types of loopbacks: Facility and Terminal. Facility loopbacks troubleshoot ports only and
are generally performed locally or at the near end. Terminal loopbacks test ports and spans and are often
used for remote sites or far-end equipment. You can provision loopbacks through CTC.
Caution
The CTC permits loopbacks to be performed on an in-service circuit. This operation is service-affecting.
Note
XTC-28-3 cards only support facility loopbacks on DS-1 circuits.
Procedure: Clear the LBKFACILITY Condition on the XTC-28-3 Card
Step 1
Double-click the reporting card in CTC or right-click the reporting card in CTC and choose
Open
from
the menu.
Step 2
Click the
Maintenance
tab:
a.
If the condition is reported against an XTC-28-3 card, also click the
DS1
tab.
b.
If a Loopback Type column cell that displays Facility (Line) is not shown under the
DS1
tab, then
click the
DS3
tab to reveal a Loopback Type column cell that displays Facility (Line).
Step 3
Click the Loopback Type column cell that displays Facility (Line).
Step 4
Click
None
, and click
Apply
.
14.4.81 LPBKFACILITY (OC-N)
•
Not Alarmed (NA) (Condition)
A loopback facility (LPBKFACILITY) alarm means a software facility loopback is active for a port on
the reporting card. Loopback is a commonly used troubleshooting technique. A signal is sent out on a
link or part of the network and returned to the sending device. A troubleshooter can compare the quality
of the sent signal and the returned signal to determine the condition of an isolated circuit. By setting up
loopbacks on various parts of the network and excluding other parts, a troubleshooter can logically
isolate the source of the problem. For more information on loopbacks, see the
Two types of loopbacks are available: Facility and Terminal. Facility loopbacks troubleshoot ports only
and are generally performed locally or at the near end. Terminal loopbacks test ports and spans and are
often used for remote sites or far end equipment. You provision loopbacks using CTC.
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 ...