What upgrade and reboot sequence should be used to upgrade all Cisco SD‑WAN controllers and WAN Edge devices?

The correct upgrade sequence for Cisco SD-WAN components is critical to maintain network stability and control plane functionality. Starting with vManage ensures that the central management platform is updated first, allowing it to manage the subsequent upgrades. Next, vBond is upgraded, as it's the orchestrator responsible for initial authentication and onboarding of devices. Following vBond, vSmart controllers are upgraded; these are the brains of the control plane, distributing policies and routing information. Finally, the WAN Edge devices are upgraded. This order minimizes disruption by ensuring that the control and orchestration planes are fully functional and compatible before the data plane devices are touched. Upgrading WAN Edge devices first or in an incorrect order could lead to control plane instability or device isolation.