Best Practices for Upgrading Edges Deployed as Hub and Spoke

While performing upgrades for Edges deployed in Hub and Spoke configurations:

• The Edges configured as a Hub should be upgraded to 3.X before upgrading the Edges configured as Spokes.
• Tunnel formation will not occur if the Hub is in a 3.X based profile and all the Spokes are running in a 2.X based profile.
• In order to overcome the above-mentioned restriction, each Spoke profile should have at least one Spoke running in the 3.2.1 based profile.