Format and Upgrade Juniper EX4200

While repurposing some old Juniper switches I found the easiest way of upgrading them was just to format and install the new image.

What you need:

• USB drive formatted as FAT32
• JUNOS image, "jinstall-ex-4200-15.1R4.6-domestic-signed.tgz" is used in this example

Copy the JUNOS file to the USB drive and connect the USB drive to the EX switch. While connected to the console, reboot the switch and press the space bar when prompted to get to the loader> prompt.

    Hit [Enter] to boot immediately, or space bar for command prompt.

Enter the following command to start the format and upgrade:

   loader>install --format file:///jinstall-ex-4200-15.1R4.6-domestic-signed.tgz

Once the format and upgrade is complete (around 15 minutes) you'll see a login prompt which you can login as root with no password. From there you can initiate the ezsetup or enter the cli.

    mgd: ----------------------------------------------------------
    mgd: Please login as 'root'. No password is required.
    mgd: To start Initial Setup, type 'ezsetup' at the JUNOS prompt.
    mgd: To start JUNOS CLI, type 'cli' at the JUNOS prompt.
    mgd: ----------------------------------------------------------
    .
    .
    .
    Login: