Hello, I am having an issue with IPv6 NETMAP on a multiwan router using nftables v0.9.8 on kernel 5.10.13-1. We are using ULAs internally for all our LAN hosts to load-balance IPv6 connections over multiple ISPs. Externally, we have 3 ISPs. We are using IPTABLES NETMAP to map our internal IPs to each external IPv6 IP prefix. This works great for IPv6 load-balancing. We can use policy based routing to route certain hosts and certain destinations through particular ISPs. However, we have an issue with connections from the outside reaching internal hosts. Outside connections only work when accessing the IP range of WAN1, which is the default gateway on the router. Incoming connections through WAN2 and WAN3 fail when WAN1 is the default gateway. If I change the default gateway to WAN2, then incoming connections work through the WAN2 IPv6 range. I ran tcpdump to see what's going on, and it appears connections come in over WAN1/WAN2/WAN3 and go out over WAN1 (or whatever the default gateway is) regardless. This causes dropped packets. With respect to NETMAP, how can I have incoming connections over WAN2 go back out through WAN2, WAN3 through WAN3, etc... Is this possible? Thank you.
