Here's my "starting position": I have a Raspberry Pi 3b+, which is already configured, and I wanted to convert it into an Access Point. I followed this tutorial: https://pimylifeup.com/raspberry-pi-wireless-access-point/ and the access point is up and running. The ip-address-distribution also works, I set the range from 172.16.0.20 to 172.16.0.30 with 255.255.255.0 and a lease time of 12h.
My goal is to connect my smartphone to the access point of the raspberry and to be able to access a specific (internal?) website which can be resolved on Port 5000 (172.16.0.3:5000).
If the raspberry is connected to my laptop with a lan-cable (and the laptop has an ip-address in this range, it currently has 172.16.0.4 - I set it manually), I'm able to access the website with my laptop.
But when I'm connected with my smartphone, I do get an ip-address, but I can't connect to the website.
Why is that so? I'm getting the right ip-address, why am I not able to "call" this website?
In step 19, a command for creating an iptables-setting is described. I also added that iptables-command, although I don't even want a wifi connection. Is it possible, that this might be the mistake? How can I solve it?
This is the first time I'm working with a raspberry / iptables / access-points, so a (if possible) simple answer would be great!
If I have expressed myself inaccurately, notify me. I'll try to answer upcoming questions as good as possible.