Support Support Downloads Knowledge Base Service Request Manager My Juniper Community

Knowledge Base

Search our Knowledge Base sites to find answers to your questions.

Ask All Knowledge Base Sites All Knowledge Base Sites JunosE Defect (KA)Knowledge BaseSecurity AdvisoriesTechnical BulletinsTechnotes Sign in to display secure content and recently viewed articles

[SRX] How to upgrade Junos OS on a Chassis Cluster



Article ID: KB17235 KB Last Updated: 05 Mar 2017Version: 20.0

This article explains how to upgrade Junos OS on SRX Chassis Cluster.

  • SRX is in a cluster
  • Junos OS upgrade must be done on both nodes in the Chassis Cluster


SRX devices in a Chassis Cluster have a requirement to not have different version of Junos OS on each node of a cluster.  Because of this, we need to ensure that both devices in the cluster come online at the same time. The recommended procedure requires CLI access (either via console, Telnet, or SSH):

  1. Install the software on each cluster member (on node0 and node1), using the CLI command (but don't reboot):
      request system software add <JUNOS package> no-copy unlink

              unlink - (Optional) On J Series Services Routers and SRX devices,this option ensures that the software package is removed
                                                at the earliest opportunity in order to make room for the installation to be completed.    

              Note: Don't reboot until you have performed the above command on each cluster member.

       2.  Simultaneouslyenter the following command on each node:

       request system reboot

Note:  This procedure cannot be used via J-Web.

Additional helpful High Availability upgrade references:

  KB17947   How to upgrade SRX Chassis Cluster with minimal downtime
  KB20959   [ISSU] Overview and Procedural Steps for In-Service Software Upgrade
  KB17946   ISSU Upgrade limitations on SRX High End Firewalls
  KB15389   What logs to collect when a problem occurs while performing ISSU (In Service Software Upgrade)
  KB17410   How to: Copy a file from one node to the other node in a JSRP Chassis Cluster
  KB16652   SRX Getting Started - Junos Software Installation/Upgrade

Related Links

Comment on this article > Affected Products Browse the Knowledge Base for more articles related to these product categories. Select a category to begin.

Security Alerts and Vulnerabilities

Security Alerts and Vulnerabilities Product Alerts and Software Release Notices Problem Report (PR) Search Tool EOL Notices and Bulletins JTAC User Guide Customer Care User Guide Pathfinder SRX High Availability Configurator SRX VPN Configurator Training Courses and Videos End User Licence Agreement Global Search