DHCP servers

[akis_t]

I have two ISPs and two separate modems. Each modem has its own DHCP. The DHCP on each modem is hardcoded to give out itself as gateway (makes sense).

Because of ISP issues I switch between ISPs by disabling one DHCP and enabling the other.

But this is tedious. What if I had an independent DHCP that would point to the required modem?

So I have two routers/switches/WAPs. Each can be configured as a DHCP. But I cannot configure them because they both "understand " the DHCP to point to their WAN port and not to their LAN ports. That would require their LAN to be different to their WAN so they can do the "routing".

This is how I understand the problem. Is there a way around it?

 

[JackMDS]

What you call a Modem is actually a Modem/Router.

The usual solution is to use a Modem only configuration and feed it to a Dual WAN Router.

Example - http://www.amazon.com/TP-LINK-TL-R4...QBN8/ref=sr_1_1?ie=UTF8&qid=1444771880&sr=8-1

Then, if you need Wireless you connect a Wireless Router configured as an Access Point to one of the Router's LAN port.

Using Wireless Routers (or Modem/Wireless Router) as a Switch with an Access Point - http://www.ezlan.net/router_AP.html

 

[akis_t]

I have three WAP/routers and they all have their own DHCP server, but while I can specify the IPs that it hands out, it is hardcoded to supply a gateway of itself, which is not what I want. I was hoping there was a way around that so that I could use one of these three WAP/routers to be my central DHCP server.

 

[RadiclDreamer]

The easiest way since what it seems like what you are wanting is dual ISP failover would be to get a dual WAN router.
You can get a lower end one for a few hundred bucks like this one

http://www.amazon.com/Peplink-Balance-20-Dual-WAN-Router/dp/B0042210U6

 

[mxnerd]

Like what JackMDS & RadiclDreamer said, what you need is dual WAN router.