While somewhat similar to the Routing menu, the MultiWAN Routing menu allows you to direct outbound traffic in multiwan scenarios.
This menu lets you define advanced parameters to make a connection bind to a specific WAN. Where outbound traffic is directed will implicitly affect the corresponding (inbound) return traffic. A packet going to WAN0 should return only via the same interface.
On: When checked, this enables the routing rule on that line of the table.
Protocol: This lets you choose the transport protocols that will be matched by the rule. There are hundreds of layer 4 protocols. This menu and setting refer to only the most common ones.
Source Address: Filters in the defined source of traffic. All filters in all LAN devices. The IP setting allows you to define a specific IP address or set of addresses using a netmask syntax (e.g. 192.168.1.0/24), where MAC binds the rule to a defined MAC Address only.
Destination Address: Similar to the source IP, the destination address makes the rule more restrictive based on/or destination address. This can be defined as ALL (as in Internet), IP address or set of addresses, defined in a netmask format or even a destination domain.
Select WAN: (WANx) - Here, you choose the logical interface where the defined outbound traffic will be directed.
Description: In this field, you can enter any notes you wish to make management easier.
Rules defined will take precedence over any WAN's weight-related setting.