Sorry that I am not entirely following.
You configure the non-meraki VPN once, and any branch that is configured in the Availability option, will build an individual IPsec-tunnel. With that you have a very small config even for a large amount of branches.
Doesn't the idea of building individual tunnels to each branch contradict the idea of a "very small config"? I.e. could a set of 20+ individual VPN tunnels be called a "very small config" even if they're configured similarly?
(We are essentially asking the MSP to build and maintain a fairly large number of individual tunnels on their side - all because we on our side can't route single VPN tunnel traffic to/from our branches? That doesn't quite make sense to me.)
Your non-meraki VPN-Hub still needs to be configured to accept the session from all branches.
What is a "non-Meraki VPN-hub"? I've poked around searching for it, and not seeing much. Native Azure VPN gateway SKUs all seem to be site-to-site, i.e. there isn't a way to configure a single one to connect to multiple endpoints in a hub-like fashion., and you pay separately for each one you set up. Similarly, most other S2S VPN gateways seem to be set up in a similar fashion: separately configured individual tunnels vs. anything resembling a "hub".
P.S. It seems (to this VPN/networking rookie) that setting up one VPN tunnel from our HQ to the MSP using non-Meraki tech e.g. a standalone Aruba S2S appliance is all there should be to it:
- Meraki will see it as a direct-attached subnet, and thus allow to route traffic to/from it, including to/from Auto-VPN sites
- the MSP only has to maintain one tunnel
- we only have to maintain that one appliance and the associated tunnel with its routing and ACLs
(At least that's what I am seeing suggested on the interwebs when searching for "connect a non-Meraki VPN peer to Auto-VPN sites".)
P.P.S. Granted, the above (using a non-Meraki VPN appliance configured outside of Meraki) falls outside of the OP question scope:
What is the best practice to connect a non-Meraki VPN peer (e.g. our Azure or AWS services) to our auto-VPN sites (networks)?
... but then so does the vMX.
I.e. the answer to the OP question ("what is the best practice...") seems to be a "no, Meraki does not appear to offer a good, simple way to connect a non-Meraki VPN peer to auto-VPN sites, however the simplest way to do this is using a non-Meraki S2S VPN gateway - especially if the number of auto-VPN sites is large enough."
Thanks!