I seem to be getting some DHCP server conflicts in my local network as I've tried to improve WiFi coverage.
My current setup is two R7800's; a main router running latest stable OpenWRT (not hnyman's) and an AP running the exact same setup, just in dumb AP mode.
I've then tried to add a TP-Link Archer C64 to the network to improve coverage, running the stock OEM software as I know OpenWRT isn't supported for that device (which, tbh, might be the source of my problems).
My plan was to just run the C64 in AP mode with a static IP and DHCP off and go about my day, but that doesn't seem possible. Annoyingly the DHCP server is on by default, even in AP mode, and turning it off seems to break the network.
My expectation was, that with authoritative set to 1 on the main router, that would be the source of truth in terms of DHCP servers and there wouldn't be a problem. But when I turn the C64 on, I see that is the source of IP assignment, rather than the main router.
Is there any way to force OpenWRT to use its DHCP server even if it detects another one on the network? My thinking is that if I can do that, then I can turn the DHCP server off on the C64 and assignment would still work fine.
Please let me know if any of this doesn't make sense and I'll try and add more context.
The OpenWrt router is using it's own DHCP server, the clients are the ones listening to two DHCP servers, and accepting the info from the bad one. Definitively, you need to disable the DHCP server on the AP.
Clients will listen to any dhcp offers on the network and will probably continue with the fastest. There isn't a way to tell them that OpenWrt is the legit dhcp and the C64 is rogue.
If you can adjust the dhcp server on C64 to advertise the OpenWrt as router and dns with distinctive address pools, you could run them in parallel. But it seems to be much easier to disable the dhcp on C64.
Thanks both for the replies - as you say, what I'm looking for doesn't really exist.
Having written this out and rubber-ducked slightly, I have a few more ideas I can try this weekend to try and can report back. But I'm already thinking if simply binning off the C64 for something that is OpenWRT compatible (maybe even another R7800) would be a simpler solution - even if it's more expensive.
I've finally had a chance to take a look at this again (an empty house).
What I thought would work, did work!
I disconnected the TP-Link from the network, reset it, and then set it up in AP-mode with DHCP disabled. I then had to restart the main router (to flush the DHCP) and it started assigning IP addresses absolutely fine.
Didn't take long at all! This is definitely the way I should've done it before, instead of introducing a third party router to the network after the fact.
