Create howto-cluster-runtime-upgrade-template.md

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Author: bartpinto

articles/operator-nexus/howto-cluster-runtime-upgrade-template.md

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+---
+title: "Azure Operator Nexus: Cluster runtime upgrade template"
+description: Learn the process for upgrading Cluster for Operator Nexus with step-by-step parameterized template.
+author: bartpinto 
+ms.author: bpinto
+ms.service: azure-operator-nexus
+ms.date: 04/24/2025
+ms.topic: how-to
+ms.custom: azure-operator-nexus, template-include
+---
+
+# Cluster runtime upgrade template
+
+This how-to guide provides a step-by-step template for upgrading a Nexus Cluster designed to assist users in managing a reproducible end-to-end upgrade through Azure APIs and standard operating procedures. Regular updates are crucial for maintaining system integrity and accessing the latest product improvements.
+
+## Overview
+
+**Runtime bundle components**: These components require operator consent for upgrades that may affect traffic behavior or necessitate server reboots. Nexus Cluster's design allows for updates to be applied while maintaining continuous workload operation.
+
+Runtime changes are categorized as follows:
+- **Firmware/BIOS/BMC updates**: Necessary to support new server control features and resolve security issues.
+- **Operating system updates**: Necessary to support new Operating system features and resolve security issues.
+- **Platform updates**: Necessary to support new platform features and resolve security issues.
+
+## Prerequisites
+
+1. Install the latest version of [Azure CLI](https://aka.ms/azcli).
+2. The latest `networkcloud` CLI extension is required. It can be installed following the steps listed in [Install CLI Extension](howto-install-cli-extensions.md).
+3. Subscription access to run the Azure Operator Nexus Network Fabric (NF) and Network Cloud (NC) CLI extension commands.
+4. Target Cluster must be healthy in a running state.