Access to an external local network through a wi-fi router

Question

ASUS

Background: there is an ASUS RT-G32 wi-fi router, a twisted pair is connected to it via WAN with the hostel's local network and the Internet, but with this connection only the internal network between our laptops and the global network is available.
When connected via LAN, respectively, there is an external local network, but without the Internet.

Problem: actually, a subject, naturally, with the Internet. Once I tried to set it up, it turned out that everything was available through the LAN port, but the connection often crashed, and after a couple of hours it stopped connecting at all, I had to return everything back.

PS: I changed the firmware, the router receives the IP and dns automatically, in the system wireless connection there are also automatic parameters.

Bonus: a less important, almost imperceptible problem - p2p connections, made through port-forwarding, but nothing comes out, it is quite possible that they are disabled by default by university admins (as well as access to online games is disabled).

I really hope for your help!

Answer 1

In general, with static routes, it should be like this (if we have 10.0.0.x locale):
1 route:
IP address of the network or host: 10.0.0.0;
Netmask: 255.0.0.0;
Gateway: 172.25.0.1;
Route 2:
Network or host IP address: 172.25.103.0;
Netmask: 255.255.255.0;
Gateway: 172.25.0.1;
3 route:
IP address of network or host: 224.0.0.0;
Netmask: 255.0.0.0;
Gateway: 172.25.0.1;

Answer 2

By WAN at the entrance LAN + Internet.
By LAN and Wi-fi, get what is at the WAN input.
Router settings get the address via DHCP or static.
Whether to use DNS forwarding of the router here is an amateur.
In clients, the connection properties are as follows.
1. The IP address that the router issued via DHCP, well, or from the same range, but statically clogged.
2. The default gateway is indicated here automatically or we indicate the IP address of the router ourselves.
3. On even DNS, there are also options here. :) If we use the DNS forwarding of the router (some router manufacturers have buggy DNS forwarding in the firmware, then we just turn it off) and then the IP address of the router will be indicated in the DNS, otherwise the provider's DNS will be registered in the DNS. Well, another option is to specify yourself, for example, the Google DNS server (8.8.8.8 and 8.8.4.4)
What are the pitfalls here? Well, for example, if the router does not automatically receive routes in a normal way, then it will be necessary to register them in the router.
You also need to look at the firewall settings in the router, what is allowed and what is not, etc.

Answer 3

Show current route table

Answer 4

What was the end of the matter? Did it work or not?

Answer 5

temporarily-permanently solved the problem in a very perverse way ... connected the host cable to Lan and shorted the WAN and LAN with another short cable ...
wan lan1 lan2
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