Juniper JUNOSE 10.0.X PHYSICAL LAYER, Configuration Manual

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host1(config-controll)# controller sonet 5/0
host1(config-controll)# path 12 ds3 1 loopback local
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Use the no version to turn off the loopback.
■
See path ds3 loopback.
path ds3 t1 loopback
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Use to configure a loopback at the T1 over T3 layer.
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Specify one of the following options:
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local —Loops the router output data back toward the router at the T1 framer;
on supported line modules, also sends an alarm indication signal (AIS) out
toward the network.
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network { line | payload }
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Specify the line keyword to loop the data back toward the network before
the T1 framer and automatically set a local loopback at the HDLC
controllers.
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Specify the payload keyword to loop the payload data back toward the
network at the T1 framer and automatically set a local loopback at the
HDLC controllers.
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Example
host1(config-controll)# path 12 ds3 2 t1 14 loopback network line
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Use the no version to clear the local loopback configuration.
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See path ds3 t1 loopback.
Enabling Remote Loopback Testing
You can configure the router to request that compatible devices connected at the
following layers enter into a loopback:
■
T1 over SONET/SDH VT layer
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T1 over T3 layer
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T3 layer
You can also configure the router to start loopback testing when it receives an
appropriate signal from a devices connected at any of these layers.
For a list of the modules that support remote loopback, see ERX Module Guide,
Appendix A, Module Protocol Support .
NOTE: There is no protocol that allows remote loopback on E1 links.
To enable remote loopback:
Testing Interfaces
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Chapter 4: Configuring Channelized OCx/STMx Interfaces