Enabling Local, Network, And Payload Loopback; Enabling Remote Loopback - Juniper PHYSICAL LAYER - CONFIGURATION GUIDE V11.1.X Configuration Manual

JUNOSe 11.1.x Physical Layer Configuration Guide

Enabling Local, Network, and Payload Loopback

To enable local, network, or payload loopback testing of a T3 or E3 line, use the
clock source and loopback commands from Controller Configuration mode.
1.
2.

Enabling Remote Loopback

You can enable remote loopback capability on frame-based T3 interfaces configured
to use C-bit framing. Remote loopback is not supported on E3 ATM, E3 FRAME, and
T3 ATM interfaces.
For a list of the modules that support remote loopback, see ERX Module Guide,
Appendix A, Module Protocol Support.
To enable remote loopback:
1.
2.
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Testing Interfaces
2^11 Pseudorandom test pattern, 2047 bits in length
2^15 Pseudorandom test pattern, 32,767 bits in length
2^20 Pseudorandom test pattern, 1,048,575 bits in length
2^20-QRSS Pseudorandom QRSS test pattern, 1,048,575 bits in length
2^23 Pseudorandom test pattern, 8,388,607 bits in length
alt-0-1 Repetitive alternating test pattern of zeros and ones, 01010101...
Specify the duration of the test in the range 1–1440 minutes.
Example
host1(config-controll)#bert pattern 2^11 interval 10
Use the no version to stop the test that is running.
See bert.
Change the clock source to internal.
host1(config-controll)#clock source internal module
Specify a loopback.
host1(config-controll)#loopback local
Change the clock source to internal.
host1(config-controll)#clock source internal module
Ensure that the line is configured to use C-bit framing, which is the default for
frame-based T3 interfaces.
host1(config-controll)#framing c-bit