Enterasys Networks X-PeditionTM manual XSRconfig#controller t1 1/0 XSRconfig-controllerT1-1/0#

Troubleshooting T1/E1 & T3/E3 Links

Figure 4-3 T1/E1 & T3/E3 Physical Layer (Layer 1) Troubleshooting Flowchart

Loss of Signal	Loss of Signal/Loss of Frame	Loss of Frame
	Use the following commands to		No		Is the
	bring up the controller:
				framing format
	controller t1 x
				correct?
	framing
						Yes

Are the cables	No
and connectors
ok?
Yes

Connect or replace the cable

Use the following commands to

change the LBO:

cablelength long/short (T1)

cablelength (T3)

If your T1/E1 or T3/E3 controller still

does not function as desired,

contact your service/network provider

The show controller command displays current controller parameters, status and statistics data. Most controller errors are caused by incorrectly configured lines including line coding, framing, and clock source parameters.

When a T1/E1 or T3/E3 controller (port) is created with an associated channel or channel group, it can exist in three states:

•Administratively down:

If you do not enter the no shutdown command when you create the controller (port) or enter the shutdown command for an already created controller (port), you create all associated channel-groups on that controller (port) but they are disabled.

•Down:

If you enter the no shutdown command for the controller in Controller mode, all associated channel groups are enabled on the physical level but the controller senses an alarm on the line and will not pass user data.

•Up:

Only when the associated interface is enabled using the no shutdown command in Interface mode does the channel-group become operational. This is because there is one-to-one mapping between channel groups and interfaces; if an interface is administratively down so is its channel group - even if the controller port is up!

Follow these steps to restart the controller to correct this type of error:

1.Enter Controller mode. For example:

XSR(config)#controller t1 1/0 XSR(config-controller<T1-1/0>)#

4-8 Configuring T1/E1 & T3/E3 Interfaces