This article shows how to perform an ISSU (In-Service Software Upgrade) on a Nexus Data Center switch (7000 and 7700 models) and avoid service and network disruption. We explain the importance of keeping your NX-OS software updated, how the upgrade process is executed, explain the purpose of the Kickstart and System images, provide methods on how to transfer the NX-OS images to the switch bootflash on both supervisor engines, verify ISSU capability and test/simulate the upgrade process.
In addition we cover useful commands to discover issues that might occur during the upgrade process, configuration backup methods, upgrading a Nexus 7000 and Nexus 7700 series with single or dual Supervisor Engines (SUP1 and SUP2 models).
Here is a quick overview of what’s covered:
- Why Upgrade your Nexus 7000/7700 NX-OS Software
- What is an ISSU Upgrade?
- How The ISSU Upgrade works
- Understanding Nexus Kickstart and System Images
- Transferring Images to Nexus 7000/7700 Switch
- Configuration Backup
- Incompatible Configuration Check, Verifying ISSU Capability, Testing The Upgrade Process
- Performing the Nexus ISSU Upgrade
- Nexus Upgrade Verification – Supervisor Engines and Modules
- Summary
Why Upgrade Your Nexus 7000/7700 NX-OS Software
Upgrading your NX-OS can be a daunting task as there is always the risk something might go wrong. Despite this, it is very important to ensure your core Nexus switch is running one of the latest and supported images.
If you’re looking for reasons why to take the risk and upgrade, here are a few that might help convince:
- Old NX-OS images might be stable but usually contain a number of bugs and security vulnerabilities that can put your core network and organization in risk.
- Your NX-OS version might not be supported any more. This means that in an event of a failure or problem, Cisco Technical Assistance Center (TAC) might require you to upgrade to a supported NX-OS version before providing any support.
- Support of new features, services and technologies. By upgrading to a newer NX-OS you’ll be able to take advantage of newer features that will now be supported.
- Support of new Modules and Supervisor Engines. When considering upgrading your Nexus Supervisor Engines or adding new modules it’s likely an upgrade will be required to support them.
- Peace of Mind. Knowing you’re on a supported, tested and patched up version always helps sleeping better at night!
It’s always recommended to perform a thorough research of the NX-OS version under consideration to identify caveats or issues that might affect your production environment. This information can be found on Cisco’s website or by opening a Cisco TAC Service Request.
What is an ISSU Upgrade?
The ISSU upgrade process provides us with the ability to upgrade a Nexus 7000/7700 switch without network or service disruption. During the ISSU process all Nexus modules and Supervisor Engines are fully upgraded without requiring a switch reboot.