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Configure Junos OS on the QFX5120


QFX5120 Default Configuration

Each QFX5120 switch is programmed with a factory-default configuration that contains the values set for each configuration parameter when a switch is shipped. The default configuration file sets values for system parameters such as the system log and file messages.

When you commit changes to the configuration, a new configuration file is created that becomes the active configuration. You can always revert to the factory-default configuration.

This topic shows the factory-default configuration file of a QFX5120 switch:

Connect and Configure a QFX5120 Switch

We ship the QFX5120 switch with Junos OS preinstalled and ready to be configured when the switch is powered on. You must perform the initial configuration of the QFX5120 through the console port (labeled CON) on the rear panel of the switch by using the command-line interface (CLI).

Before you begin connecting and configuring a QFX5120, set the following parameter values on the console server or PC:

  • Baud Rate—9600

  • Data—8

  • Flow Control—None

  • Parity—None

  • Stop Bits—1

  • DCD State—Disregard

Gather the following information:

  • The name the switch will use on the network

  • The domain name the switch will use

  • The IP address and prefix length information for the Ethernet interface

  • The IP address of a default switch

  • The IP address of a DNS server

  • The password for the root user

This procedure connects the switch to the network, but does not enable it to forward traffic. For the complete information about enabling the switch to forward traffic, including examples, see the Junos OS configuration guides.

To configure the software:

  1. Verify that the switch is powered on.
  2. Connect the console port to a laptop or PC.
  3. Log in as the root user. You don't need to enter a password.
  4. Start the CLI.
  5. Enter configuration mode.
  6. Set the root authentication password by entering either a clear-text password, an encrypted password, or an SSH public key string (DSA or RSA).




  7. Configure the name of the switch. If the name includes spaces, enclose the name in double quotation marks (“ ”).
  8. Create a user account.
  9. Set the user account class to super-user.
  10. Configure the domain name of the switch.
  11. Configure the IP address and prefix length for the Ethernet interface on the switch.
  12. Configure the IP address of a backup router, which is used only while the routing protocol is not running.
  13. Configure the IP address of a DNS server.
  14. (Optional) Configure the static routes to remote subnets with access to the management port. Access to the management port is limited to the local subnet.
  15. Configure the Telnet service.
  16. (Optional) Display the configuration to verify that it is correct.
  17. Commit the configuration to activate it on the switch.
  18. (Optional) Configure additional properties by adding the necessary configuration statements. Then commit the changes to activate them on the switch.
  19. When you have finished configuring the switch, exit configuration mode.