Multi WAN without NPt
I am currently plan to roll out IPv6 with Multi WAN. I know the wiki page, but I wonder whether I can do real IPv6 Multihoming (RFC 7157 Scenario 2). Has anyone tried it yet?
I've not seen anyone attempt anything other than NPt or using a routing protocol like BGP.
I don't know of anyone doing that, but it's possible to configure if both prefixes are static. The RA config can advertise multiple subnets, but can only do so today if they're both static. Then you should be able to policy route by source network out the correct ISP.
Source address selection by end hosts is possibly a bigger impediment. Client machines generally would only use one or the other. It's probably less problematic with servers with static IPs, such as if you want multi-WAN redundancy to the same internal system on native IPs of both.