I have a couple MX65s I requested for POC. I've come to the conclusion that Meraki SD-WAN and likely all SD-WAN will not be suitable for my company's use case. I want to double check with the experts though. My use case= Multicast video via RTP. So, you can run multicast over a private line (MPLS, VPLS in my case) no problem, but of course you can't multicast over the public internet. You can't build a GRE on the MX itself, and if you put it in passthrough mode, that takes away the other WAN port. I'm guessing you may be able to passthrough to a router and the router can build a GRE through the MX VPN? Even so, this would leave an MX for each WAN with no actual WAN auto failover between the two WANs.
To clarify, my interest in SD-WAN is mitigating errors in video in an efficient way. Currently we use event manager for failover to backup router and manual failover back to primary. Also, two VPLS is not an option as we are trying to save money as well.
Am I missing something? Can you Multicast through a private link with DIA as backup with auto failover at a branch site by any means?