
Using Synchronous Leased Lines 19-9
Troubleshooting a Leased Line Connection
• If you still have problems, enter the following commands:
Command> set debug 0x51
Command> set console s1
Then set the CSU/DSU for local loopback. You should see the following message:
LCP_APPARENT_LOOP
For more information about the interpreting the results of the debug command, 
refer to the PortMaster Troubleshooting Guide. 
• If the local loopback shows network connectivity in the local router, take the 
CSU/DSU out of loopback and set line loopback on the remote CSU/DSU. If the 
remote loopback test does not show network connectivity in the remote router, the 
problem is either in the configuration of one of the CSU/DSUs or in the line itself.
• When you finish, enter the following commands to turn off the debug utility:
Command> set debug off
Command> reset console
• Contact your carrier to review your configuration and the status of their line.