These servers are meant for everyone. each server has capacity of 500 people.
Ingame chat is sketchy so hope these help. Also so you can reach each other from freep/creep.
Default Server Host/Ip: 220.127.116.11
Dwarrow 2: port 3785(general chat)
Dwarrow 3: port 3786(Raiding/Instances)
Dwarrow 4: port 3787(Freepside)
Dwarrow 5: port 3788(Creepside)
Dwarrow 6: port 3789(w/e)
Dwarrow 7: port 3790(w/e)
You can use any of these for anything. Theres enough open channels for each server. Just a recommendation on their uses. Just dont spy on each other during pvp I guess. Should also use your ingame names so people know who you are. Or not. Up to you. Since its public..use at own risk.
Have fun grouping. Or not.
You can track server status at ddservers.guildlaunch.com
there you can view all servers and who is currently using each one.