That is an architectural decision you need to make. None of the answers are wrong. Find what suits your setup best.  ... View more

@jimmyt234 @cmr @Dalleman Thanks for responding. Conclusion: Failover of Meraki to Non-Meraki IPSec tunnels from Primary to Secondary can be achieved by TAG method mentioned. Better Option: Install a Meraki behind remote DC in customer 2 premises. Thanks a lot for your responses.   ... View more

Horrible.  I don't envy you.  I am going to refer to "your" as Company A", and "their" and "them" as "Company B".   I think the best solution (most probable to work and with the most flexibility) will be to get an additional MX and put it into their DC in VPN concentrator mode.  Place it next to their Aryaka SD-WAN box. Then you can put routes in either SD-WAN pointing to the other SD-WAN.   You could also consider getting them to put an Aryaka SD-WAN box in your DC next to your MX for the most flexibility.   Then you can use the Meraki Site to Site VPN Translation feature linked to by @ww . ... View more