https://documentation.meraki.com/Architectures_and_Best_Practices/Auto_VPN_Hub_Deployment_Recommendations
This is the number of tunnels that each hub needs to support in a hub-and-spoke Auto VPN deployment with two NAT-mode hubs with dual uplink connections and 50 remote sites with a single uplink connection. This can be calculated by using the formula for the hub tunnel count in a hub-and-spoke topology1:
Hub Tunnel Count = (H x (H - 1) / 2 x L1) + (H x S x L1 x L2)
Where H is the number of hubs, S is the number of spokes, L1 is the number of uplinks for the hubs, and L2 is the number of uplinks for the spokes. In this case, H = 2, S = 50, L1 = 2, and L2 = 1. Therefore,
Hub Tunnel Count = (2 x (2 - 1) / 2 x 2) + (2 x 50 x 2 x 1) Hub Tunnel Count = (2 x 1 / 2 x 2) + (200 x 2) Hub Tunnel Count = (2 / 2 x 2) + (400) Hub Tunnel Count = (1 x 2) + (400) Hub Tunnel Count = 2 + 400 Hub Tunnel Count = 402
This question is related to the topic of Auto VPN Hub Deployment Recommendations in the Cisco Meraki documentation. You can find more information about this topic in the Auto VPN Hub Deployment Recommendations article or the Meraki Auto VPN General Best Practices page.
