3Com 3C8S5007 - SuperStack II PathBuilder S500..., User Manual

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ROUBLESHOOTING
LPBCK !<path> -PATH RMLnLpbck
■
To receive data from the network, extract the payload from the
frames, and then reframe the payload and loop back the data to the
network, configure a remote payload loopback by entering:
LPBCK !<path> -PATH RmPyldLpbck
3 The loopback is now enabled and will remain enabled until explicitly
ended. To end a loopback in progress, use:
LPBCK !<path> -PA STOP
Failure to perform this step causes the port to remain in loopback mode
preventing connectivity through the port. Performing diagnostics on the
port will reveal only that the port is down.
4 Enable the path using:
SETDefault !<path> -PATH ConnControl=Enable
Response to
Loopback
Assertions from
Link Partner on
Flex-WAN Serial
and Ultra-WAN
CSU/DSU Interfaces
This section describes the PathBuilder switch response to various link
partner loopback assertions.
Response to Local
Loopback Assertion
on a Flex-WAN Serial
Interface
If the PathBuilder switch is connected to a DTE that asserts a local
loopback signal, the PathBuilder switch displays:
Path x Detected DTE Loopback ON, switching to echo mode
The PathBuilder switch in echo mode transmits the received data back to
the DTE.
When the signal is removed, the PathBuilder switch displays:
Path x Detected DTE Loopback OFF, switching to normal mode