Minecraft is not a hardware-intensive video game. However, there are key points you should consider if you plan to run your server. RAM is the first thing you'll encounter. You'll need approximately 1GB RAM for each four to five people who will be using your server. Your Internet connection is your primary roadblock.
Your first stop: CanIHostaMinecraftServer.com. This website will tell you how many players you can support simultaneously. If that number is a bit low, consider renting space on a dedicated Minecraft server-or having fewer friends.
There are many servers hosts to choose. A quick Google search will help you get started. Before you choose one, it is important to determine how many players will be on your server and how much money.
If you'll be hosting only a few friends, you can run a Minecraft server on your own hardware; the process is fairly simple. If you plan to install your server on a Windows machine, head over to the Minecraft downloads page and grab the executable. Download the server.jar file from the same webpage if you plan to run your server on a Mac, Linux or Windows machine. (Note: If you plan to run this in Ubuntu, use the Windows server download link.)
Regardless of whether you're using Windows or Mac/Linux for your operating system, you should dump the downloaded file into its own folder. This is because it creates configuration files on its own during operation. Double-click on the executable in Windows. It will immediately start creating a world and populating the world with critters.
It takes a little more work to use the Mac/Linux option. On either platform, first make sure that you have the latest version of Java installed. This task can be done by Macs via software update. Java's Download Page can be used to download the appropriate Java version for your distribution.
Once you've installed the latest version of Java, you'll need to tell the Minecraft server how much memory to allocate to the server. Feel free to skip to the section of this how-to that's appropriate for your system; Windows users can jump straight to "Getting Your Friends In."
Linux Users
Open the terminal in Linux. Instructions may vary by distribution, but you'll probably find it in the Applications menu, under Accessories. Navigate to your Minecraft server folder (cd NAME OF YOUR FOLDER), and type the following command:
java -Xms1024M -Xmx1024M -jar minecraft_server.jar nogui
This will allocate 1GB of RAM for your server. If you're using the 32-bit version of Java, 1GB is your limit. If you're using 64-bit Java, the limit is 1GB. For example, 2048M can be used to allocate 2GB and 4096M to allocate 4GB.
Mac Users
If you're on a Mac, open the TextEdit application, and type (or copy and paste) the following lines of code.
exec java -Xmx1G -Xms1G -jar minecraft_server.jar
Allocate as much memory as you'd like by changing '1G' to the number of gigabytes you'd like to set aside (2G for 2GB, 4G for 4GB, and so on).
In the Format Menu, select Make Plain Text, save the file as start.command, and move it into your server folder. Next, go to the Terminal. Type chmod +x and drag the start.command file into the Terminal. It will grant the file appropriate permissions. Finally, double-click the start.command key to start your server.
Invite your friends to join you
Every player who wishes to participate in the Multiplayer event must choose the Multiplayer option from Minecraft's main menu. To instruct Minecraft to remember details, players can choose between Direct Connect (for a temporary visitor) or Add Server (for permanent connection). If everyone is on the same network, they can simply type localhost into the server address field. To connect to friends remotely, you'll need your external IP number. Enter "What is mine IP address" into Google to see the information you need in a box just above the results.
Sharing your single-player world of single-player with friends
In your Minecraft server folder, look for the file named 'server.properties' and open it with your favorite text editor. The Minecraft Wiki provides an extensive guide to configuring your Minecraft server. This article will focus on how to transfer a world that you have been playing on to the Minecraft server you just created.
The first step in creating a world is to find it. In Windows, click the Start button, and type " %appdata% " (without quotation marks but with spaces fore and aft) and press Enter. The '.minecraft' folder should be right at the top. Your world will be in the Saves folder; copy that folder into the folder that contains your Minecraft server. Look for the line that says 'levelname=world.' Change the name of your world to 'world.properties' in the server.properties. Your creation will be available for anyone who has access to your server the next time you fire it up.
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