How can 30 machines connect to the router without a switch?

Add information for all devices.

Yes, I see.

Look at how these 30 switches are distributed. If it's a topic, it's easy. Hehe ~ ~

We connect 30 PCs to the 48-port switch on the second floor, and then connect the 48-port switch to the WAN port of the router. The PC automatically gets the address.

Set the WAN port address of the router connected to the switch to X.X.X.X 255.255.255.0.

The IP address of another WAN port on the router is set to the IP address assigned by the school.

Configure DHCP address pool on the router. The address pool size allocation is ≥30, and the gateway is set as the IP address of the WAN port interconnected with the switch. Other DHCP parameters are the default values.

Router Hill also needs to be configured with NAT translation, the source of NAT translation is the network segment of the intranet, and the purpose is the address assigned by the school.

Ok, now everyone can get high. Ha ha ha ha ~ ~

I hope I can help you ~