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Installing Software on a Mixed Virtual Chassis with EX4200, EX4500, and EX4550 Switches (CLI Procedure)

You can use this procedure to upgrade or downgrade Junos OS for all member switches in an any operational mixed Virtual Chassis composed of any combination of EX4200, EX4500, or EX4550 switches.

To upgrade Junos OS for an operational mixed Virtual Chassis:

  1. Download the same version of Junos OS software for each switch in the mixed Virtual Chassis.

    You must download Junos OS Release 11.4 or later if you have three or more EX4500 switches in your mixed Virtual Chassis.


    EX4500 and EX4550 switches run the same Junos OS. You only need to download one Junos OS image if you are running a mixed EX4500 and EX4550 Virtual Chassis.

  2. (Optional) Back up the current software configuration to a second storage option. See the Junos OS Installation and Upgrade Guide for instructions on performing this task.
  3. (Optional) Copy the software packages to the member switch acting in the primary role. We recommend that you use FTP to copy the file to the /var/tmp directory.

    This step is optional because Junos OS can also be upgraded when the software image is stored at a remote location. These instructions describe the software upgrade process for both scenarios.

  4. Install the new packages on the Virtual Chassis:

    You enter the request system software add set [package package] command once on the Virtual Chassis to download the software package onto all member switches in the mixed Virtual Chassis. If your mixed Virtual Chassis includes at least one EX4200 members switch, ensure that the package path points to one EX4200 Junos OS image and, one EX4500 Junos OS image.

    You only need to download one EX4500 switch Junos OS image to upgrade a mixed Virtual Chassis because a Junos OS image for an EX4500 switch can be used to upgrade EX4500 and EX4550 switches.

    Replace package with one of the following paths:

    • For a software package in a local directory on the switch—/var/tmp/package.tgz.

    • For a software package on a remote server:

      • ftp://hostname/pathname/package.tgz

      • http://hostname/pathname/package.tgz

    where package.tgz is, for example, jinstall-ex-4200-11.1R1.8-domestic-signed.tgz.


    To terminate the installation, do not reboot your Virtual Chassis; instead, finish the installation and then issue the request system software delete package.tgz command, where package.tgz is, for example, jinstall-ex-4500-11.1R1.8-domestic-signed.tgz. This is your last chance to stop the installation.

  5. Reboot the Virtual Chassis to start the new software:
  6. After the reboot has completed, log in and verify that the new version of the software is properly installed for all member switches in the Virtual Chassis: