What revision of what core are you using? It's all pretty straight forward after you barebone the code a little; if you open worldserver.conf and authserver.conf and read through it it will teach you a lot of what you need to know. If you have any questions and don't know what it is then you should post questions to those conflicts. A few bare essentials to running your own server.
Understanding Ports: Ports are a gateway to your computer, the standard ports that need to be opened on a router are
Code:
HTTP:80
RealmListen:3724
MySQL:3306
Realm:8085
RA: 3443
Sorry if I'm missing any that's all I can think of off the top of my head though
I ended up having to open up 3036 and 6112 which I haven't fully understood what those had to be opened for, but that's meh lol.
If you want a more detailed explanation feel free to ask and I can make a guide for it, but I'll want to know what core you are using at the bare minimum. I don't know too much on Arcemu I'm usually more into Mangos and Trinity, but I could figure out Arcemu if someone needed the help.