Hello, i've setup a Pihole on a small machine (not using PiOS but debian) and i've a pre-configured network with a lot of devices using the routers own DNS and DHCP. I'm planning to use a lan-cable connected hotspot/wifi adapter and only let the clients connected to the hotspot use Pihole.
When i enable DHCP on the raspberry pi, the whole network and the connected hardware could be messes.
My idea is to connect the hotspot through ethernet to my pi-hole device (i've got 3 eth interfaces) and route the whole traffic of the hotspot through my setup pihole.
Is that possible without?
How could i achieve the goal of using an external hotspot connected to the network as pihole without messing around with the other connected devices (that are connected through lan).
That's a networking question rather than a Pi-hole one, and a device specific at that.
The answer would entirely depend on the capabilities of that hotspot:
It has to present itself to its clients as their router, while it connects to your main router as a client at the same time, and your Pi-hole is best connected to that hotspot's network.
You should consult your hotspot's documentation and support channels for its configuration details.
You mean on an additional Raspberry Pi?
Yes, but you'd need to configure that RPi as a router, e.g. by installing RaspAP or a full router OS.
If you instead want to run Pi-hole on that same machine:
There is certainly more than one way to achieve this, and there are users that have succeeded running Pi-hole on an RPi acting as wireless AP, see e.g.RaspAP && PiHole , and RaspAp + Pi-Hole - #2 by Bucking_Horn might also be relevant.
However, those posts may not be up to date.
And as such a configuration is not a Pi-hole issue at all, you should specifically check alternative sources for running an RPi as wireless AP.
Note that any AP would have to offer DHCP services to its clients, and as Pi-hole is also capable of doing this, the most likely source of trouble would lie in the configuration of pihole-FTL/dnsmasq, Pi-hole's embedded DHCP server.
If your designated AP software also runs dnsmasq, you'd have to find a way to disable that in your AP, and you'd have to deal with any configuration conflicts from files located in /etc/dnsmasq.d/.