How to connect two routers

One or two devices are used as routers.

The connection mode is as follows:

ADSL----Routing a WAN port----LAN Port-----Routing b WAN port----LAN Port----Computer

This way connecting two devices all work in routing mode, router A's LAN port IP address can be 192.168.0.1

While router B changes the address of the LAN, it cannot be in the same network segment as the front-end router A, and can be changed to 192.168.1.1;

Second device is a router and another device is a switch

The connection mode is as follows:

ADSL----Routing a WAN port----LAN Port-----routing b LAN port----LAN Port----Computer

In this connection, you do not use the WAN port of Router B, you also need to change the address of the LAN. Do not conflict with the management address 192.168.0.1 of front-end router A, you can set to 192.168.0.2, you are on the same network segment, but do not repeat, and be sure to turn off the DHCP server for router B.