Assuming all CAT 5e cords are perfect (I made them and have even redone the ends to make sure they were making a proper connection)
I have my main cable modem. From that modem it connects to my router, then from that router I have it connected to a switcher, from that switcher I have it connected to a wireless router.
Works perfectly except for one thing. My first router works perfect wirelessly and wired. Next in line, the switcher also works perfectly I have five CAT 5 cords running from it to wired PC's and they connect to the internet perfectly. The third device, the wireless router, does not allow internet connectivity. It shows up on my wireless laptop and other devices, but when I try to connect, it does not work.
I replaced the switcher with a linksys router, and that router connected my PC's WIRED perfectly and also gave a working WI-FI signal. Then from that we hooked another wireless router and still no signal.
No matter how we do it, switcher to wireless router or wireless router to wireless router, the very last (third router) does not let us connect to the internet.
My first router assigns DHCP. The switcher just continues the connection. The third device, the wireless router, we have turned off DHCP.
If the third router is connected by its WAN port to the prior switch (i.e., WAN to LAN), it MUST have its DHCP server enabled because you've created a new subnet behind that router. You would only disable its DHCP server if connected LAN to LAN since then they would be considered part of the same subnet and must share the same DHCP server.
That said, most home users are only using multiple routers for switching purposes, so your routers and switches should be LAN to LAN. The ONLY router that should be using its WAN port is the one connected to the modem because that’s the only one actually doing any routing to another network (i.e., the Internet).