You must log on as admin before typing admin commands. Both logon and admin commands have to be...How to use a URL (domain name) instead of IP-address?
If you own your domain, you can redirect it or a subdomain to your game server IP - meaning you...MineCraft Server OP Commands
Server/op Commands Minecraft Operator-only commands Before using an OP command...Setting up permissions (GroupManager) with McMyAdmin.
When it comes to Minecraft permissions, there are approximately a dozen alternatives you can use....Getting Started with your server - basics
Assuming you are rather new at administrating a Minecraft server and easily want to get started...