Example: Configuring a T1 Interface

This example shows how to complete the initial configuration on a T1 interface.

• Requirements
• Overview
• Configuration
• Verification

Requirements

Before you can create an interface, you must install a PIM, connect the interface cables to the ports, and power on the device.

Overview

This example describes the initial configuration that you must complete on each network interface. Within the example, you configure the t1-1/0/0 interface as follows:

• You create the basic configuration for the new interface by setting the encapsulation type to ppp. Enter additional values for physical interface properties as needed.
• You set the logical interface to 0. Note that the logical unit number can range from 0 to 16,384. Enter additional values for properties you need to configure on the logical interface, such as logical encapsulation or protocol family.

Configuration

Step-by-Step Procedure

To configure an T1 interface:

1. Create the new interface.

   [edit]user@host# edit interfaces t1-1/0/0

2. Create the basic configuration for the new interface.

   [edit interface t1-1/0/0]user@host# set encapsulation ppp

3. Add logical interfaces.

   [edit interface t1-1/0/0]user@host# set unit 0

4. Commit the configuration if you are done configuring the device.

   [edit interfaces t1-1/0/0]user@host# commit

Verification

To verify an interface configuration, perform these tasks:

• Verifying the Link State of All Interfaces
• Verifying Interface Properties

Verifying the Link State of All Interfaces

Purpose

By using the ping tool on each peer address in the network, verify that all interfaces on the device are operational.

Action

For each interface on the device:

1. In the J-Web interface, select Troubleshoot>Ping Host.
2. In the Remote Host box, type the address of the interface for which you want to verify the link state.
3. Click Start. Output appears on a separate page.

Sample Output

PING 10.10.10.10 : 56 data bytes
64 bytes from 10.10.10.10: icmp_seq=0 ttl=255 time=0.382 ms
64 bytes from 10.10.10.10: icmp_seq=1 ttl=255 time=0.266 ms

Meaning

If the interface is operational, it generates an ICMP response. If this response is received, the round-trip time in milliseconds is listed in the time field. For more information about the output, see the Junos OS Administration Guide for Security Devices.

Verifying Interface Properties

Purpose

Verify that the interface properties are correct.

Action

From the CLI, enter the show interfaces detail command.

Meaning

The output shows a summary of interface information. Verify the following information:

• The physical interface is Enabled. If the interface is shown as Disabled, do one of the following:
  • In the CLI configuration editor, delete the disable statement at the [edit interfaces t1-1/0/0] level of the configuration hierarchy.
  • In the J-Web configuration editor, clear the Disable check box on the Interfaces> t1-1/0/0 page.
• The physical link is Up. A link state of Down indicates a problem with the interface module, interface port, or physical connection (link-layer errors).
• The Last Flapped time is an expected value. The Last Flapped time indicates the last time the physical interface became unavailable and then available again. Unexpected flapping indicates likely link-layer errors.
• The traffic statistics reflect expected input and output rates. Verify that the number of inbound and outbound bytes and packets matches expected throughput for the physical interface. To clear the statistics and see only new changes, use the clear interfaces statistics t1-1/0/0 command.

Related Topics

• Junos OS Feature Support Reference for SRX Series and J Series Devices
• ping in the Junos System Basics and Services Command Reference.
• show interfaces detail in the Junos Interfaces Command Reference
• Configuring T1 Physical Interface Properties in the Junos Network Interfaces Configuration Guide
• Configuring E1 Physical Interface Properties in the Junos Network Interfaces Configuration Guide