One more thing.
Note: MX devices in Routed mode only support OSPF on firmware versions 13.4+, when using the "Single LAN" LAN setting. OSPF is otherwise supported when the MX is in passthrough mode on any available firmware version. This can be set under Security & SD-WAN > Configure > Addressing & VLANs.
Note: The MX will only advertise Meraki Auto VPN routes. The MX does not learn routes advertised by any OSPF neighbors.
Note: To achieve symmetrical routing between spoke MXs participating in AutoVPN and OSPF peers, the hub MX will need to have static route(s) configured for any subnets local to the OSPF peer, which will have to be advertised in the AutoVPN mesh (by switching the VPN mode for those particular static rotue(s) to Enabled).
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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