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Configuring Junos OS on the EX9200

EX9200 Switch Default Configuration

Each EX9200 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 Address Resolution Protocol (ARP) aging timer, the system log, and file messages, while also enabling the Link Layer Discovery Protocol (LLDP) protocol, the Rapid Spanning Tree Protocol (RSTP), Internet Group Management Protocol (IGMP) snooping, and storm control.

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. See Reverting to the Default Factory Configuration for the EX Series Switch.

This topic shows the factory default configuration file of an EX9200 switch.

Connecting and Configuring an EX9200 Switch (CLI Procedure)

The EX9200 switch is shipped with the Junos OS preinstalled and ready to be configured when the switch is powered on. There are three copies of the software: one on a CompactFlash card in the Routing Engine module (RE module), one on a rotating hard disk in the RE module, and one on a USB flash drive that can be inserted into the slot in the faceplate of the RE module.

When the switch boots, it first attempts to start the image on the USB flash drive. If there is no USB flash drive inserted into the RE module or if the attempt otherwise fails, the switch next attempts to start the software from the CompactFlash card (if installed), and finally from the hard disk.

You configure the switch by issuing Junos OS command-line interface (CLI) commands, either on a console device attached to the console (CONSOLE) port on the primary RE module, or over a telnet connection to a network connected to the Ethernet management (<...>) port on the primary RE module.

Gather the following information before configuring the switch:

  • Name the switch will use on the network

  • Domain name the switch will use

  • IP address and prefix length information for the Ethernet interface

  • IP address of a default switch

  • IP address of a DNS server

  • Password for the root user

This procedure connects the switch to the network, but does not enable it to forward traffic. For 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. Log in as the root user. There is no password.
  3. Start the CLI.
  4. Enter configuration mode.
  5. Set the root authentication password by entering either a clear-text password, an encrypted password, or an SSH public key string (DSA or RSA).




  6. Configure the name of the switch. If the name includes spaces, enclose the name in quotation marks (“ ”).
  7. Create a user account.
  8. Set the user account class to super-user.
  9. Configure the switch’s domain name.
  10. Configure the IP address and prefix length for the switch’s Ethernet interface.
  11. Configure the IP address of a DNS server.
  12. (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. For more information about static routes, see the Junos OS Administration Library for Routing Devices.
  13. Configure the telnet service at the [edit system services] hierarchy level.
  14. (Optional) Display the configuration to verify that it is correct.
  15. Commit the configuration to activate it on the switch.
  16. (Optional) Configure additional properties by adding the necessary configuration statements. Then commit the changes to activate them on the switch.
  17. When you have finished configuring the switch, exit configuration mode.

To reinstall Junos OS, you boot the switch from the removable media. Do not insert the removable media during normal operations. The switch does not operate normally when it is booted from the removable media.

When the switch boots from the storage media (removable media, CompactFlash card, or hard disk) it expands its search in the /config directory of the routing platform for the following files in the following order: juniper.conf (the main configuration file), rescue.conf (the rescue configuration file), and juniper.conf.1 (the first rollback configuration file). When the first configuration file is found that can be loaded properly, the search ends and the file is loaded. If none of the file can be loaded properly, the routing platform does not function properly. If the switch boots from an alternate boot device, Junos OS displays a message indication this when you log in to the switch.