Our hotel guests have added a lot of AP to the network segment. Sometimes one AP in the network fails and other devices find the address of the bad AP?

Most of your hotels or your guests use portable routers or fat AP. In this case, there is no good way but to find one and deal with it, and it is really difficult to find it. This is also a serious shortcoming of a single independent hotspot in the network.

So you need to use a thin AP+AC wireless network system, such as Feiyu's wireless cloud, using AC as a unified controller, and only a unique DHCP server can ban other DHCP in the network, so there will be no such problem.