Question about using a old router as an AP with two DHCP servers

I have a old Huawei Router (b315) and wanted to use it as a Access point / range extender. Right now I can’t seem to disable the DHCP server on it as it seems to break all functionality when I do so, is there any problem with having two routers both acting as DHCP servers assuming they have different address spaces. I’m also unsure if I configured it correctly, please tell me what I should change.

Here’s some more information:

Main router:
Default Gateway: 192.168.100.1
Subnet Mask: 255.255.255.0
DHCP server addresses: 192.168.100.3 - 192.168.100.254
DHCP relay is enabled but doesn’t seem to make a difference.

Second router/ap:
Default Gateway: 192.168.100.1
ip address: 192.168.100.2
DHCP server addresses: 192.168.8.100 - 192.168.8.200 (disabling it causes me to be unable to see anything on the network.)

On the router you want to use as a dedicated AP, what port(s) are you using to connect it to the network?

Consumer routers can have arbitrary limitations, so it might not be possible to use as an AP, but hypothetically it should be possible.

You don’t want to have 2 dhcp servers on the same subnet. It is possible to do this in large environments with fully configurable servers but not in your case.

Are you able to flash ddwrt or something similar? Usually you can make it work just not with the stock image

Also provide full network diagram pls

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On the router you want to use as a dedicated AP, what port(s) are you using to connect it to the network?

Using a LAN cable from the main router, and have it set up to use a static ip outside the first router’s DHCP address range.

You don’t want to have 2 dhcp servers on the same subnet. It is possible to do this in large environments with fully configurable servers but not in your case.

Can you elaborate on why this would be a bad idea if the DHCP addresses differ, I’m not that good with networks? I can setup a subnet as I don’t have many users but I kinda forgot how it works. Other than a bit going to the host side.

Are you able to flash ddwrt or something similar? Usually you can make it work just not with the stock image Also provide full network diagram pls

Unfortunately no because the old router is a huawei b315 which is not supported.

It’s setup so that both routers are DHCP servers (because I can’t disable it on the old router). The old router has an IP outside the main router’s DHCP address range where it’s ip is 192.168.100.2 (on the main network) and the main router’s DHCP range is 192.168.100.3 - 192.168.100.254. The old router is setup to request a static ip within the same subnet (192.168.100.2) and the default gateway for it is the main router’s ip (192.168.100.1).

The DHCP server address range for the old router is out of the first routers range, being from 192.168.8.100 - 192.168.8.200 ( I have no Idea why it’s working in the first place without even being a correct subnet I guess routers don’t protect people from themselves lol). Here’s the diagram:

Are the SSIDs the same? Also you might want to try something like
192.168.100.3-100 on one pool and 192.168.100.101-254 on the other. Not sure what all options your Huawei router has for configuration. You currently have them in separate networks.

The SSIDs are not the same. I’ll do that Thanks.

You could have one server dealing out 100-149, and the other 150-199 in your home /24 range

There’s nothing really wrong with that, clients connecting to the network first time will ask for an ip, get two offers, accept one, refuse the other.

Reason for so many recommendations to disable other DHCP online is to be able to simplify things, as well as devices usually having a fixed default gateway or DNS or other parameters they hand out via DHCP (other DHCP should still point to your first gateway and intended DNS which is likely the same as your gateway)