I knew the routing will only choose the nearest route. if I just put 3 LANs in NAT masquerade , it will all go out by WAN1.
What should I do to make the setup work. please help , a example will be very appreciated.
Another approach that you may want to consider is PCC load balancing. This would match each connection with a different WAN rather then breaking it up by internal subnets. You can probably achieve a more even distribution of traffic this way. This is however assuming you don’t need to associate specific internal computers with specific public ip addresses.
A vlan would give you layer 2 seporation but it wouldn’t help you sort traffic between upline providers. The bottom like is that you need a default route with a routing mark then you need to add a routing mark to all traffic that you want to use that route through a mangle rule. You could choose the mangle rule criteria based on vlan, subnet or per connection with PCC. I would still would probably do PCC load balancing because it is most likely the option that would give you the best ability to load balance until you have a nearly even distribution of traffic. If you wanted you could use a vlan and PCC.