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Cisco MGX 8230 Edge Concentrator Installation and Configuration
Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001
Chapter 6 Card and Service Configuration
DS3 Loopback Test
Configure Loopback on All DS1s in a DS3 Line
To verify that the loopback can be configured on all the DS1s of the DS3 line:
Step 1
Select a node with PXM-T3 back card.
Step 2
Configure the line using cnfln -felpbnum 29.
Step 3
Check that dsplog does not show any errors or alarms logged.
Step 4
Using dspln, check that FarEndLoopbkLineNum has been configured to be ds1lineall.
Pass Criteria:
•
No errors logged on the console or the log due to configuring loopback on all DS1 lines of PXM-T3.
•
Configured loopback can be displayed using dspln.
Receive a Loopback Request
To verify that DS3 interface can be put into loopback:
Step 1
Select a node with PXM-T3 back card.
Step 2
Make sure that the FEAC code validation criteria on the DS3 interface is not disabled using dspln -ds3
<slot>.<port>.
Step 3
Configure the HP cerjac tester to send a pattern to the DS3 interface of the node.
Step 4
Any pattern sent will cause the interface to put itself into loopback and the interface retransmits the same
pattern back to the tester.
Step 5
From the tester, verify that the same is received back on the tester, thus validating the loopback on the
DS3 interface.
Step 6
Check that dsplog does not show any errors or alarms logged.
Pass Criteria:
•
The pattern sent by the tester is received back to the tester as is.
•
No errors logged on the console or the log.
Retransmit Pattern
Loopback Activation Code
MGX 8230 Switch
with T3 Interface
DTA Tester
(Digital
Transmission
Analyzer)
46090