cannot resolve hostname and unknown host problem

[Shadaman]

hi whenever i try to input the ip address based from the server page here, i always end up getting the message unknown host or cannot resolve hostname. i am 100% that i typed it correctly, no extra spaces or anything.

i just can't get it to work.

i've tried inputing other server ip's from other websites and it works, but this is the game i wanna play

 

[Stunt_PIg]

Heres the link to hope fully fix it