Loading JunOS on an MX series router

This procedure works for SRX series devices as well.

• For reference: see Juniper knowledge base: https://kb.juniper.net/InfoCenter/index?page=content&id=KB11409

Step-by-step:

• Connect to the router's console as root user (the prompt looks like this: root> )
  • (If, right after login, you already are in shell mode (root@% ) and the exit command will only log you out instead of bringing you into command mode (root> ), you can issue the cli command to get there.)
• Check the current software version: show version
• Start a shell session: start shell (the prompt changes to root@% )
• Create a temporary folder and mount the USB drive:
  • mkdir /tmp/usb
  • Put the jinstall-*.tgz file on a FAT32 formatted USB drive and place it in the router's USB port
  • Watch the message on the screen to find out what device references the USB drive (e.g. da1s1)
    • If mounting da0s1 does not work, try re-seating the USB drive until it appears as da1s1.
  • mount -t msdosfs /dev/da1s1 /tmp/usb (if you get the message "Operation not permitted", try a different USB drive (i.e. a different manufacturer))
• Copy the jinstall file to the local file system:
  • Example: cp /tmp/usb/jinstall-ppc-14.2R7.5-domestic-signed.tgz /var/tmp/
  • Example: cp /tmp/usb/jinstall-ppc-15.1R5.5-domestic-signed.tgz /var/tmp/
• Unmount the USB drive and unplug it: umount /tmp/usb
• Exit the shell session to go back to command mode: exit (the prompt changes back to root> )
• Install the software with the command request system software add no-validate /var/tmp/[filename]:
  • The no-validate option skips validation of the current configuration to work with the new JunOS version, which is OK for new, unconfigured machines
  • Example: request system software add no-validate /var/tmp/jinstall-ppc-14.2R7.5-domestic-signed.tgz
  • Example: request system software add no-validate /var/tmp/jinstall-ppc-15.1R5.5-domestic-signed.tgz
  • Example: request system software add no-validate /var/tmp/jinstall-ppc-15.1R6.7-domestic-signed.tgz
• Reboot the router: request system reboot
• Check the new software version has been installed: show version