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[EOE/EOL] [Upgrade EX switch] Stage 3 - Upgrading EX series Devices



Article ID: KB20536 KB Last Updated: 23 Nov 2021Version: 4.0

Note: A product listed in this article has either reached hardware End of Life (EOL) OR software End of Engineering (EOE).  Refer to End of Life Products & Milestones for the EOL, EOE, and End of Support (EOS) dates.


This article documents Stage 3 – Operational Stage on Upgrading Juniper EX Switches.

Note: Most of the information detailed here is also available in Installing Software on EX Series Switches.

To go directly to other stages of Junos OS upgrade on EX switches, consult the Resolution Guide -- Upgrading EX Series.

Note: Juniper Networks recommends scheduling a downtime when performing Junos OS installation/upgrade.


  • Best practice on upgrading standalone / virtual-chassis / EX 8200 switches

  • Different procedures to upgrade switches running Junos OS

  • Upgrading Junos OS version



The third stage of Junos OS upgrade involves reviewing the "Best Practice" documentation and executing the actual commands to install the software.

At this stage, it is assumed that you have already downloaded your software package from the Juniper website and performed a backup of your configuration. If you have not done so, refer to the following articles:

For more information about the other stages, refer to Resolution Guide -- Upgrading EX Series.


Perform the following steps for Stage 3:

  1. Review the "Best Practice" documentation:

  1. Install the Junos OS software.

Important: Juniper Networks recommends scheduling a downtime when installing the Junos OS software.

J-Web (GUI)

Select the link below for the step-by-step procedure on installing the Junos OS software via J-Web.

Note about the J-Web procedure instructions:


Refer to KB20551 - [EX] Example - Installing Junos OS on an EX switch (where Junos OS is copied to the EX switch) for instructions on installing the Junos OS software via the CLI.

  1. If you encounter a problem during the installation (with the above methods), go to KB20464 - Stage 4 - Troubleshooting Upgrade Failure for troubleshooting upgrade failures.

  2. Confirm the Junos OS version that has been installed. 

  • Run the following command to verify the Junos OS version.

root@lab-4200# run show version
  • To check the previous installed version on the EX switch, run the following command:

root@lab-4200# run show system snapshot media internal slice alternate 


Modification History:

2021-11-23: Article marked as EOL/EOE. This has been already documented extensively in Technical Library documentation.


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