I'm a PC repair tech and this is a problem I've recently been trying to troubleshoot for a customer. Upstairs they have the main router which servers as the gateway and router, both hardwired and wireless. They have a dlink ethernet over power device (not sure if that's the proper term) which connects to the router/gateway upstairs which they then wanted to connect another router downstairs which they wanted to setup as a wireless repeater. Ideally the downstairs router should just be a repeater, but ignore that for now, if I can get the current situation working or understand why it doesn't then I can do that.
Ok, so the downstairs router connects to the upstairs router fine via dhcp. I would think disabling the dhcp server on the downstairs router would send the requests to the upstairs router since they're in the same subnet, but that doesn't seem to work. If I set the ips on the computers manually then they connect fine. So turning on the dhcp server the computer get addresses, they can speak to both routers, they can resolve dns queries, yet they cannot get the internet, basically they cannot get outside the upstairs router, and I'm confused as to why. Since they're getting their address information from the downstairs router the downstairs router is set as the gateway on these computers. If you change the gateway manually to that of the upstairs router then things work fine, however why would this be? What exactly is the hangup here? I get the same exact issues if setting the downstairs router to a different subnet which would rule out any possible ip conflicts, however I did verify that there were no conflicts anyhow, but checked that for good measure. I'm basically at a loss at this point. It's a fairly minimalistic router so there's not much to change, but there really shouldn't be. Am I looking at some kind of bug in the router or is there something I'm doing wrong here?