I managed to get the Wifi on the raspberry pi to work. However, when I use "hostname -i" in the terminal, it returns something like 127.1.1.1 and when I type "ifconfig" it returns something like "198.168.10.13" and when I use nmap from nmap.org it returns "198.168.10.10". So which one do I use? How do I portfoward? (The youtube videos didn't help, do I have to portfoward to the pi's IP or some other computers?) Also,Is it safe to give out your IP address like I just did? (I tried to make a static IP but I am not sure if I did it correctly, how do I check and, if it is wrong, how do I make a static ip?) Lastly, is vanilla server better then servers like Bukkit? (Sorry for all the questions, I have been working on it for weeks.)
The IP address you shall forward is the inet: one from "ifconfig" or "ip a". It is safe to share this ip, since it is a local ip address. Also you need to have a public IP address from your ISP to if you want to access the server from outside your network. To make a static ip on your ethernet, you edit your interfaces file.
sudo nano /etc/network/interfaces
And in that file edit eth0 something like this
auto eth0
iface eth0 inet static
address 192.168.10.12
netmask 255.255.255.0
network 192.168.10.0
gateway 192.168.10.1
You can check what the gateway and network ip is by typing netstat -nr