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Performing the Initial Software Configuration for the MX204 Router

The router is shipped with the Junos operating system (OS) preinstalled and ready to be configured when the router is powered on. Two 16-MB internal NAND Flash memory devices are located on the baseboard for BIOS storage. The USB storage device can be inserted into the USB slot on the chassis faceplate. The router also supports two built-in M.2-based solid-state drive (SSD) slots. These two SSD devices act as the primary boot devices (SSD0 and SSD1). When the router boots, it first attempts to start the Junos OS image on the USB flash drive if it detects one. If a USB flash drive is not inserted into the router, or the attempt otherwise fails, the router next tries the primary boot device, and then tries the secondary boot device.

You configure the router by issuing Junos OS command-line interface (CLI) commands, either on a console device attached to the CON port on the front panel, or over a Telnet connection to a network connected to the MGMT port on the front panel.

Gather the following information before configuring the router:

  • Name the router will use on the network

  • Domain name the router will use

  • IP address and prefix length information for the Ethernet interface

  • IP address of a default router

  • IP address of a DNS server

  • Password for the root user

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

To configure the software:

  1. Verify that the router is powered on.
  2. Log in as the “root” user. There is no password.
  3. Start the CLI. For more information about CLI commands, see the CLI Explorer.
  4. Enter configuration mode.
  5. Configure the name of the router. If the name includes spaces, enclose the name in quotation marks (“ ”).
  6. Create a management console user account.
  7. Set the user account class to super-user.
  8. Configure the router’s domain name.
  9. Configure the IP address and prefix length for the router’s Ethernet interface.
  10. Configure the IP address of a backup router, which is used only while the routing protocol is not running.
  11. Configure the IP address of a DNS server.
  12. Set the root authentication password by entering either a cleartext password, an encrypted password, or an SSH public key string (DSA or RSA).




  13. (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. To access the management port from a remote subnet, you need to add a static route to that subnet within the routing table. For more information about static routes, see the Junos OS Administration Library for Routing Devices.
  14. Configure the Telnet service at the [edit system services] hierarchy level.
  15. (Optional) Display the configuration to verify that it is correct.
  16. Commit the configuration to activate it on the router.
  17. (Optional) Configure additional properties by adding the necessary configuration statements. Then commit the changes to activate them on the router.
  18. When you have finished configuring the router, exit configuration mode.