Performing A Local Loopback Test On The Csu/Dsu Port (45X And 55X) - 3Com NETBuilder SI Using Manual

Performing a Local
Loopback Test on the
CSU/DSU Port
(45x and 55x)
6 To determine the current status of the loopback test, either
locally-initiated or remotely-initiated, and to determine if the V.54
loopback detection is on, enter:
SHow -SYS V54Lback
This section describes how to perform a local loopback test using the
loopback plug on the built-in 56/64 Kbps CSU/DSU on the model 45x and
55x bridge/router.
Figure 11 shows the data flow that occurs when this loopback test is
performed.
Figure 11 CSU/DSU Local Loopback Testing
Before running the CSU/DSU loopback test, attach a console or Telnet to
your bridge/router.
To perform a local loopback test on the built-in CSU/DSU, follow
these steps:
1 Uncable the WAN port and insert the loopback plug that came with your
system.
2 Set the baud rate to 56 Kbps by entering:
SETDefault !3 -PATH Baud = 56
SETDefault !3 -PATH CONTrol = Enable
3 Set the owner of the WAN port to loopback by entering:
SETDefault !3 -PORT OWNer = LoopBack
4 Select the loopback test mode by entering:
DLTest TestMode LoopBack
Performing Loopback Tests
CSU/DSU port
with loopback plug
137