raspap-webgui VS pihole-router

I also know that the RaspAP software works, because some people have used it before. https://raspap.com it's got a lot more going on than setting up an AP bare bones on the Pi, but might be easier. I haven't tried it but I know people that have.

https://raspap.com/ might be extremely helpful in your project.

To "insure" safety of our photos and minimize potential loss when we are completely offline for several days, I wanted to create a media offload station which would be a Rasperry PI with SSD storage, UPS and an LTE modem. I would like our phones to connect to Raspberry-hosted wifi network, sync photos wirelessly via Syncthing and then - when there is internet connection - to our home NAS - that's the easy part.

RaspAP doesn't currently support WPA2-Enterprise, although it certainly could if there's enough demand for it. You're welcome to open a feature request.

RaspAP: https://raspap.com

Turns out this was a bug introduced in the latest RPi OS kernel. You were the first to report it. A fix has been pushed in the latest release. Thanks for the heads up...and your patience. https://github.com/RaspAP/raspap-webgui/releases/tag/2.9.0

For PiHole, do you mean PiHole as router, something like this?: https://github.com/JVital2013/pihole-router

I don't think this is what you want, but it is a pihole on a router.

This. will do what you want. My ISP is Comcast and I own my router. Please note that the link is for a Rpi-4, it is Linux and will work on any Linux OS software. This week rebooted my Pi after 158 days of up-time. My RPi has a fan and a GOOD power supply. I connect as IPv4 and IPv6.

You might set the AT&T router to passthru mode. However, this will require you to setup a stand alone router. Such as. This example uses Pihole for the DHCP and ad blocker. I use this on my home network without the pihole. I use dnsmasq for DHCP server. I ran this for about 6 months and works well.

This is essentially my setup without the Pihole. I use dnsmasq and have it setup as a DHCP but have a pihole on another RPi-3. I run to Unifi AP's for wifi.

This might help. It is a Rpi router running pihole. See this. There are rules in the firewall that might help.

Or try something in Linux like this. Instead of PiHole use dnsmasq as the DHCP software.

See this. for a start. I don't run the Pihole on my router but I do use the Pihole engine, dnsmasq, as my DHCP for my internal lan.

Something like this. Add dnsmasq for a dhcp server, both IPv4 and IPv6, full firewall. Add dhcpcd to get IPv4 and IPv6 from your Internet provider. Add a vpn on the router so you can connect via a encrypted phone connection. Use a Ethernet dongle for the second interface. If you have an access point add that to your setup and turn off the Wifi on the RPi. Add VLANS.

See this URL. The Wifi from the RPi-4 will connect to the ArubaAP.