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 begin, install a PIM, connect the interface cables to the ports, and power on the device. See the Getting Started Guide for your device.

Overview

This example describes the initial configuration that you must complete on each network interface. In this 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. You can 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 through 16,384. You can enter additional values for properties you need to configure on the logical interface, such as logical encapsulation or protocol family.

Configuration

CLI Quick Configuration

To quickly configure a T1 interface, copy the following commands and paste them into the CLI:

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For instructions on how to do that, see Using the CLI Editor in Configuration Mode.

To configure a T1 interface:

1. Create the interface.

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

2. Create the basic configuration for the new interface.

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

3. Add logical interfaces.

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

Results

From configuration mode, confirm your configuration by entering the show interfaces command. If the output does not display the intended configuration, repeat the configuration instructions in this example to correct it.

For brevity, this show interfaces command output includes only the configuration that is relevant to this example. Any other configuration on the system has been replaced with ellipses (...).

If you are done configuring the device, enter commit from configuration mode.

Verification

To confirm that the configuration is working properly, 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. The output appears on a separate page.

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

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.

Meaning

Verifying Interface Properties

Purpose

Verify that the interface properties are correct.

Action

From the operational mode, enter the show interfaces detail command.

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. It 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 input and output 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 Documentation

• Junos OS Feature Support Reference for SRX Series and J Series Devices
• Junos OS Administration Guide for Security Devices
• Junos System Basics and Services Command Reference
• Junos Interfaces Command Reference
• Junos OS Network Interfaces Configuration Guide
• Understanding T1 and E1 Interfaces
• Example: Deleting a T1 Interface