R3303-HP HSR6800 Routers Interface Command Reference

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[Sysname] controller cpos 2/0/0
[Sysname-Cpos2/0/0] e3 1 set clock master
e3 set loopback
Use e3 set loopback to enable a type of loopback on the specified E3 channel.
Use undo e3 set loopback to disable loopback.
Syntax
e3 e3-number set loopback { local | payload | remote }
undo e3 e3-number set loopback
Default
Loopback is disabled.
Views
CPOS interface view
Default command level
2: System level
Parameters
e3-number: Number of an E3 channel on the current CPOS interface, in the range of 1 to 3.
local: Enables internal loopback on the E3 channel.
payload: Enables external payload loopback on the E3 channel.
remote: Enables external loopback on the E3 channel. This keyword is not supported in the current
software version. This field is reserved for future support.
Usage guidelines
You can troubleshoot an E3 channel by placing it in a loopback. The following are loopback modes
available for you to test an E3 channel to different depths:
• In an internal loopback, transmitted data loops back to the receiver end internally without being
sent to the line.
• In an external payload loopback, transmitted data loops over the far end and back to the receiver
end after through the E3 framer.
• In an external loopback, transmitted data loops over the far end and back to the receiver end
before going through the E3 framer.
Examples
# Enable external payload loopback on E3 channel 1 on interface CPOS 2/0/0.
<Sysname> system-view
[Sysname] controller cpos 2/0/0
[Sysname-Cpos2/0/0] e3 1 set loopback payload
Related commands
display controller cpos e3