Is it possible using NAT only on specific condition

Enig123 · September 5, 2020, 2:53am

Now my DIR-860L B1 running OpenWRT is configured as WiFi AP at address 192.168.1.2, and the 2 WiFis configured at 172.16.2.0/24 and 172.16.3.0/24, no nat involved, and the router configured with a static route for the data get back to WiFi clients.

While I intended for WiFi client to access a server in the LAN 192.168.1.0/24, it will get into asymmetrical routing, the request went direct to the server, while the response from the server will go through the router.

My idea is to using NAT for WiFi client only when visiting servers in the LAN 192.168.1.0/24 range. How can I configure my WiFi AP to achieve that purpose?

I've tried writing rule in /etc/firewall.user but no clue how, or even it's possible to do it there. Also I am not sure if it is possible, and how to do that.

Any ideas? Helps?

vgaetera · September 5, 2020, 3:19am

https://openwrt.org/docs/guide-user/firewall/firewall_configuration#zones

Name Type Required Default Description

masq_src list of subnets no 0.0.0.0/0 Limit masquerading to the given source subnets. Negation is possible by prefixing the subnet with !; multiple subnets are allowed.

masq_dest list of subnets no 0.0.0.0/0 Limit masquerading to the given destination subnets. Negation is possible by prefixing the subnet with !; multiple subnets are allowed.

Name	Type	Required	Default	Description
`masq_src`	list of subnets	no	`0.0.0.0/0`	Limit masquerading to the given source subnets. Negation is possible by prefixing the subnet with `!`; multiple subnets are allowed.
`masq_dest`	list of subnets	no	`0.0.0.0/0`	Limit masquerading to the given destination subnets. Negation is possible by prefixing the subnet with `!`; multiple subnets are allowed.