8-16
Cisco Broadband Local Integrated Services Solution Troubleshooting Guide
OL-5169-01
Chapter 8 Troubleshooting the Cisco Catalyst 6509
Troubleshooting Serial Lines
Terminating a BER test
To terminate a BER test, type
no t1 t1-line-number bert
where t1-line-number is 1–28.
Example:
• Terminate the BER test running on T1 line 10 on the CT3 line card.
Router(config)# controller T3 1/0/0
Router(config-controller)# no t1 10 bert
Using Loopback Tests
The following sections describe the configuration and use of loopback tests in problem isolation:
• Configuring the Loopback Mode for a T3 Controller, page 8-16
• Configuring a T3 Controller to Respond to Remote Loopback Commands, page 8-17
• Configuring the Loopback Mode for a Gigabit Ethernet Interface, page 8-17
• Configuring the Loopback Mode for an OC-12 POS Interface, page 8-17
Configuring the Loopback Mode for a T3 Controller
You can configure the loopback modes for a T3 controller by using the loopback command:
loopback [local | network | remote]
The default loopback mode for the T3 controller is no loopback.
To return the T3 controller to its default condition, use the no form of the command.
Examples:
• Configure a T3 controller for local loopback:
Router(config)# controller T3 1/0/0
Router(config-controller)# loopback local
Local loopback simultaneously loops all channels toward the router and transmits a T3 AIS to the
network. You can use local loopback to diagnose problems with the port when isolated from the
network cables.
• Configure a T3 port for network loopback:
Router(config)# controller T3 1/0/0
Router(config-controller)# loopback network
Network loopback loops the T3 line back towards the network and can be used to diagnose problems
with cables from the central switching office to the port.
• Configure a T3 port for remote loopback:
Router(config)# controller T3 1/0/0
Router(config-controller)# loopback remote
Remote loopback sends a command to loop the T3 line at the far end (central office). It can be used
to diagnose problems with cables from the port adapter to the switching office.
Commentaires sur ces manuels