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Initial Router or Switch Configuration Using Junos OS

This topic provides an overview of initial network device configuration tasks using Junos OS.

When you turn on a device for the first time, Junos OS automatically boots and starts. You must enter basic configuration information so the device is on the network and you can log in to it over the network.

To configure the device initially, you must connect through the console port.

When you first connect to the console of a device that has not yet been configured, log in as the user root. At first, the root account requires no password. You can see that you are the user root, because the command prompt shows the username root@#.

You must start the Junos OS command-line interface (CLI) using the command cli. The command prompt root@> indicates that you are the user root and that you are in Junos OS operational mode. Enter Junos OS configuration mode by typing the command configure. The command prompt root@# indicates that you are in the Junos OS configuration mode.

When you first configure a device, you should configure the following basic properties:

  • Device hostname

  • Domain name

  • IP address of the device management Ethernet interface. To find the management Ethernet interface that you should use for configuration, see Supported Routing Engines by Router.

  • IP address of a backup router

  • IP address of one or more DNS name servers on your network

  • Password for the root account