This article will serve you well https://documentation.meraki.com/MX/Deployment_Guides/VPN_Concentrator_Deployment_Guide#:~:text=Use%20Uplink%20IPs%20is%20selected,the%20virtual%20IP%20(vIP).&text=The%20virtual%20uplink%20IPs%20option,shared%20by%20the%20HA%20MXs. Uplink IPs Use Uplink IPs is selected by default for new network setups. In order to properly communicate in HA, VPN concentrator MXs must be set to use the virtual IP (vIP).
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