Tutorials/Setting up a server

This tutorial takes you through the steps of setting up your own server using the default server software that Mojang distributes free of charge. The software may be installed on most operating systems, including Windows, Mac and Linux.

For more tutorials, see the bottom of this page or the Tutorials page. For more information on Minecraft servers, see the Server page.

Notes:
 * Setting up a server takes some time, and some technical knowledge. Don't try to set up a server unless you have some basic computer and networking abilities. Probably, your best bet can be to look on the Internet for a guide on how to set up a server.
 * A Minecraft server does not need to be a high-end machine, but netbooks and notebooks don't usually make for good server machines. They typically have lower-end hardware and bad I/O performance in comparison to desktop computers.
 * Hosting and playing on the same machine is also possible, if your computer is powerful enough.
 * Having many players in a wireless network (WLAN and especially WWAN) is not recommended. Use a wired network instead, such as Ethernet.
 * If you decide you don't want to host, but still want to play online, check out the public server options in the Minecraft servers area of the Minecraft forum.
 * If you still want to manage a server, but not from home, check out the Minecraft server hosting area of the Minecraft forum or other websites. Expect to pay monthly for this type of server since finding free hosting is a rarity. But you save the hassle of constantly maintaining a server and having is on-line for your players.

Note: There is also custom server software available, which most large servers use, but these applications are not supported by Mojang.

Warning
Since you're about to run your own server, you should be aware of the possible dangers. Running by the instructions below should not put you at any risk, but this is a wiki which everybody is allowed to edit, and we don't know about your system configuration, so we cannot guarantee you'll be out of danger.

In order to run your server and stay out of trouble, we strongly recommend you should at least know about the following:
 * Using the command-line and editing configuration files
 * Networking in general (IP, DHCP, ports, etc.)
 * Your system configuration
 * Your network configuration
 * Your router configuration (if you want other people to connect over Internet)

Alternatively, if you decide that you don't wish to create your own server, you are welcome to join other servers, many can be found on the Minecraft Forum server list.

Verify that the latest version of Java is installed
The Minecraft server requires the Java Runtime Environment (also called JRE or simply Java). For your security, you should only use the most recent version of Java. To verify that you have the latest version, do one of the following:


 * Open Windows Control Panel, find Java (it may be inside the Programs category), and click on Update Now.
 * Visit http://java.com/en/download/installed.jsp. This will perform an automatic version check from your browser. However, the Google Chrome browser does not run Java content and therefore cannot check Java through this browser.
 * Open a command window and enter the command . If a version number is reported, then check the Java website to see what the most recent version number is.

If you don't have Java, or your version is outdated, then download it at http://www.java.com/download/.

Starting the Minecraft server
Begin by downloading the server software from the Minecraft download page. The server is available as a Java .jar file.

Before starting the server, be aware that wherever you run the server from (your desktop, a download folder, etc.), it will create several configuration files in that location. It's better to create a dedicated folder for your server, and run it from inside that folder, as this will make it easier to locate/organize all the files.

Double click the file and the server should start. It will write configuration files in the folder, and quit immediately.

The first, and required, configuration you have to do is accepting the EULA. A text file call eula.txt is created in the application folder. Open this file in a text editor and change the line  to. It signifies that you have read and understood the end user license agreement that you'll follow when using the software. If you don't do this, the server will shut down immediately when you try to start it.

If you get an error such as "Can't save server.properties" and your screen fills with useless, gibberish text, then run the Minecraft Server as administrator by right-mouse clicking on it and choosing 'Run as administrator'. (You may need the administrator password to do this.)

You might want to customize the server configuration, as is explained below.

Configuring from the command line
Both the Java and the executable version can be run from the Windows command prompt/line with extra parameters to configure, for example, memory usage. As we currently know there is no command prompt for java on the Windows platform that will run these commands correctly. That however is subject to change.

To start the server, change to the Minecraft server folder (find the file path to which your server's jar file is) and open the windows command prompt (in Start, just type cmd and it should have a file name of cmd.exe), then enter the following command:

Replace  with the server application file name, for example.

If you prefer not to use the server's Graphical User Interface (GUI) to enter administration commands, simply add the option  to the end of the command:

Some people have reported that this requires (significantly) less memory and CPU resources.

You can also replace the  command with. Javaw.exe is identical to Java.exe but there is no associated console window. This may be preferable when using a .bat file. (See the next section.) Note however that Javaw also doesn't show any error messages in the command window if anything is wrong.

Using the  and   parameters, the initial and maximum memory size for Java can be specified. By default, your server runs with about 100 MB of RAM, which is very little. Most people will change their server to run with more, for example:



Add in  if your server is on a 64-bit computer using 64-bit Java.

Add  to tell the server to run in online mode so only authenticated users can join.

Creating a .bat file to store the commands
To start the configured Minecraft server, without having to enter all commands every time, you can create a .bat file in the server folder. You can include the  command to tell the window to stay open after the /stop command is issued. Useful if you want to read what happened as it shut down.

Here is an example of a bat file:

java -Xms1024M -Xmx2048M -jar minecraft_server.jar nogui pause

Double click the file to start your server. You may get a "Class_Not_Found" and ServerGuiConcole error, just ignore these errors and you should see your "Server Thread/INFO" dialog start the server.

Further configuration
Read the sections Port forwarding and further for more information about configuring your server.

OS X instructions
A three step in-depth video tutorial of the process can be seen here. Keep in mind that the server won't run correctly on OS X 10.4 and may crash your machine.

Downloading
Download the latest server application software from the download page.

Installing Java
OS X already has Java downloaded onto your machine. Java is updated through Java's website If you are running OS X 10.8.* (Mountain Lion) or OS X 10.9.* (Mavericks) You need to download Java here, as Mavericks will fail when looking for it. no Java Download

Setting up the Minecraft server
Ensure you have followed the download step before proceeding.


 * Create a folder, if you haven't already, and put minecraft_server.jar into it. For example, create a folder on the Desktop named minecraft_server and drag the jar file into it.
 * Open TextEdit, set the format to plain text (Format > Make Plain Text), copy and paste in the following:
 * Save the file as "start.command" in the same folder as minecraft_server.jar.
 * This will give the server enough RAM to run. The amount of RAM can be changed by editing the  to something else, such as   for 2 GB.
 * Open Terminal (in /Applications/Utilities/Terminal).
 * Grant execute permissions on file start.command to Owner, Group. and Public. To do so, type in , with a space after it; drag and drop the start.command file into the terminal window; and then press enter. (This gives run permission to the start.command script.)
 * Double-click the start.command file to start the server.
 * A new Terminal window will open and, the first time you run the script, several error messages about missing files/directories will appear. This is normal. You're now ready to configure your server.

Using Time Capsule
Some homes use AirPort Time Capsule as a wireless router instead of other brands. This section will teach you how to set one up without messing up your file server.

NOTE: Make sure you have your admin username and password.

That's it! You're now ready to configure your server.
 * Open System Preferences > Network.
 * Click the Advanced button and go under TCP/IP.
 * Where it says Configure IPv4, change that option to Using DHCP with manual address.
 * Change the IP address to 10.0.1.x, where x is a number between the last number of the two numbers under DHCP range (i.e. 10.0.1.2 to 10.0.1.254 would be anywhere between 2 and 254).
 * Now go to the Sharing section and make sure that Internet Sharing is on.
 * Now, open up AirPort Utility and edit your Time Capsule settings.
 * Go under Network and make sure the option Router Mode is set to DHCP and NAT. Now, click the + button under the Port Settings.
 * Type in the following:
 * Description: Minecraft Server (or whatever you want to call it)
 * Private IP Address: The address you chose for the 4th step.
 * Change everything with the word port in it to 25565.
 * Now hit Save and update the Time Capsule.

Linux instructions
This tutorial for how to set up a Minecraft server on Linux was designed for people who don't have a lot of experience with Linux. There is a outdated but more advanced tutorial in the forums.

This tutorial was tested on Ubuntu 9.10 32-bit but should work with the 32-bit and 64-bit descendants of Debian. (Note that a 64-bit version of Linux will probably perform better on a 64-bit CPU, and that a 32-bit version will only use the first 4 GiB of RAM if more than that is installed.)

Downloading
Download the latest server application software from the download page.

Installing Java
If you get  (which may be followed by more text) or if you do have another Java version than 1.6 then you need to install or update java. The official Oracle Java is recommended. A few individuals have experienced issues with OpenJDK. Others report that running on OpenJDK is completely fine.

Debian
Ensure that the non-free repository is being scanned by apt. You do this by adding non-free to your  file. e.g.:

deb http://ftp.uk.debian.org/debian/ squeeze main contrib non-free

Update your sources list (as root): apt-get update

Then to install Java, simply type this in terminal and press enter (as root): apt-get install sun-java6-jre

Ubuntu
Unfortunately, some licensing issues have prevented Canonical from allowing repositories to have Sun Java, so you must either download it directly from Oracle, package it, and install it or you could use the PPA provided by webupd8 by following the instructions below.

This guide has been tested on Ubuntu Server 12.10.

Note: You might need to install the package "software-properties-common" by running  and/or "python-software-properties" by running   to use the   command.

Run the following commands in this order to add the PPA, update the source list and then install java:

Then run this to check what version you have installed:

The output should be similar to:

For more information or troubleshooting see this link at webupd8s site

openSUSE
On older versions, you can simply type  into a terminal.

On newer versions, there is a tutorial here describing how to install Java.

Arch Linux
Open a terminal and run  as root.

Arch Linux ARMv7
On ARMv7 it could better to use java from oracle http://www.oracle.com/technetwork/java/javase/downloads/jdk7-arm-downloads-2187468.html Accept license agreement and download jdk-7u60-linux-arm-vfp-hflt.tar.gz Extract file in

and change java default with

Then

should give something like that:

(tested on Raspberry Pi 2)

Gentoo
Use:

Other distros
Alternatively, you can visit Java's website directly to download the Java package for Linux. Most distros work with this (either 32 or 64-bit). Instructions for the installation of those different packages are given on the site.

If during installation, it asks for a password, enter your password. If you get asked "Is this OK [Y/N]" Enter Y and press enter if required. Java should now be installed.

Start the Minecraft server
Open the terminal again Applications > Accessories > Terminal Enter the following commands, substituting 'minecraft_server' with the name of the folder you extracted the server to:

Less than 1GB free RAM
If you have less than 1024MB RAM, the above line may cause problems with swapping and out of memory conditions, which makes the game hard to play.

It may look like this:



You are interested in the last number in the third line, 2163 in this case. Subtract some RAM as safety. On this computer, the server may use up to 1536 MB RAM. Now, replace the 1024 in the above example with the calculated number:

Voila, it should run smoothly now

Tip: If you want to spare more memory, you may set the -Xms parameter even lower, say:

The parameter controls how much memory is reserved on startup Your server will start with 32MB RAM and whenever it needs more memory it will allocate some until it reaches the maximum of 512 MB. However, this will result in a little slowdown whenever the allocation is done.

Startup and maintenance script
Alternatively you can manage/automate the startup and shutdown of the Minecraft server using a script such as the ones listed below:


 * Minecraft Server Manager A comprehensive start up script for Minecraft and Bukkit servers (support Debian, such as Ubuntu).
 * MSM can also periodically create World Edit compatible backups.
 * Keeps players informed with configurable in-game messages, such as "Shutting down in 10 seconds!"
 * Expose in-game commands (such as "say", "op" and "whitelist") to the terminal.
 * Tab completion on all commands makes learning easy.
 * Visit Minecraft Server Manager's GitHub page for the full list of features.
 * Server startup script
 * M3tal Warrior' Server Startup Script
 * For Debian (and should work on Ubuntu too); Bukkit and Vanilla compatible
 * Full backup and rollback routines
 * All ingame commands can be invocated
 * Supports using the RAM as server root file system
 * Multiple cron invocations to ease administration
 * Easy autoupdater
 * Easy installer for first timers
 * FreeBSD startup script
 * OpenBSD startup script
 * Ubuntu startup script
 * rfwadmin startup script with web interface (for Linux servers). Nice web interface for quickly saving and loading maps.
 * Minecraft Systemd Service A fully systemd-integrated minecraft service:
 * Working on CentOS and Fedora
 * Protecting the server with various readonly and inaccessible jails
 * Safe restart and stop operations using rcon
 * Can be combined with a Minecraft Command Center Script for ease of administration
 * Arch Linux systemd wrapper

A simple installer script (also installs Java)
https://github.com/silvertriclops/MCSLI

Note: this is a very early project, designed with offline installation in mind, and will be updated periodically to make it more user friendly.

FreeBSD instructions
This part was tested with FreeBSD 10.0 amd64 and 'jre-7u65-linux-i586.tar.gz'

Installing Java
Due to performance and crash issue with OpenJDK and Minecraft server, we will install Sun/Oracle JRE made for linux. Before installing this JRE, you have to install the linux binary compatibility on FreeBSD, you can follow this documentation. Jave requires some information about the proc. You have to mount linprocfs, type: and add this line to : The Sun/Oracle JRE has a dependency marked as forbidden and the installation will fail. Go to  and in the Makefile remove the line which starts with. Next you have to manually get the linux tarball due to licence issue (like `jre-7u65-linux-i586.tar.gz') from java official web site and copy the file to. Then to install the JRE, go to  and run:

Note: The previous version of this part, tested on FreeBSD 9.2 amd64, was explained like this: You may have to set JRE_UPDATE_VERSION variable in your Makefile to the actual number (e.g. 45 like in this example) and run 'make install NO_CHECKSUM=1'.

Try running. You may end up with a message that it can not find. One way to fix it is to add your java paths to the search explicitly. Make a symlink: And in  add: Run. Now  should work.

Launching Minecraft Server
Create a folder and copy the minecraft server jar in it. In the actual version you will get this exception  if you run the server in the usual way, so we add this line to the command to fix that. The command to launch is like

Plan 9
Use: Then snarf java -jar  xvmf in acme

Port forwarding
Port forwarding is used when you have a router and you wish to let users connect to your server through it. If you wish to host your server for local reasons, it is not required that you do so. Keep in mind that port forwarding might cause security risks.

'''When port forwarding, it varies on how your router will ask you for the information. If you don't understand on how your router wants you to input the information, try visiting PortForward.com for a tutorial. If you still need help, please visit the Minecraft Forums and create a thread asking for help (You need to register).'''

Once you have managed to locate your router's admin page, and find the Port Forwarding page; hit add new service (may not work) (if you use Belkin, this can be very difficult to perform) or custom service. When you get a page asking to setup the new rule, it should prompt you on what you want to call it. You may name it as you wish but for simplicity, name it "minecraft". Then you want to look for "type". Select TCP. For the ports (internal and external), enter 25565. If it asks for anything else other than output IP (or internal IP, server IP), leave it alone and continue.

To find your computer's IP address, use the following steps:

Windows
 * Press ; this should being up the "Run" dialog box. Type  and hit . This should open a command window with a black background. From there, type   and press . You should be given a list of text. Scroll up to "Wireless LAN" (if using wireless) or "Ethernet" (if using a wired connection), and look at "IPv4 address". To the right of this should be a string of numbers (of the form xxx.xxx.xxx.xxx). Copy this down by right clicking the window and selecting "Mark", then highlight the area and hit Enter. Don't copy any parenthesis or letters.

Mac
 * Locate your way to your desktop. Pull up the apple menu under the logo and scroll down to System Preferences; then select "Network" your IP should be on the lower right as "IP address (xxx.xxx.xxx.xxx)". Once you have your IP, copy it down.

Linux
 * Either you use the network diagnose center (depending on distribution), or the terminal with . The output should return all your interfaces. Search for , copy the xxx.xxx.xxx.xxx numbers down.

Once you have this IP, enter it in the "Output IP / Server IP" or whatever way it asks for where the service points to.

Once you have completed it, find where it says to save/continue/apply. And you have successfully port forwarded. When you run your Minecraft server, you have to leave the Server IP field empty in the server properties.

For people to connect to your server, they must use your external IP, which you can find at websites such as IP Chicken. If you don't want to use such IPs, use DynDNS services such as NoIP DynDNS

Configure and connect
Now it is time to configure and connect.

Setting up a VPN
An alternate way to set up a server between you and your friends is to set up a VPN (virtual private network). This method may be deemed unrecommended, and an inconvenience for many users due to the fact that all users whom wish to connect to the server must download external software in order to join or create server. An alternative to this method is to port forward. A free software utility that can be used to set up a VPN ais Hamachi by LogMeIn. OpenVPN is another (free, open source) alternative that supports most OSes, but is a bit more difficult to configure. The free version of Hamachi allows up to 5 connections (i.e. players).

Setting up Hamachi

 * 1) Install Hamachi on each computer that wishes to participate in the server, including the host.   Windows / Mac   Linux (32-bit and 64-bit   and   packages are available, you can install it on Gentoo by emerging "net-misc/logmein-hamachi")
 * 2) The host server signs up for admin via the Logmein website.
 * 3) On the host machine, a new Hamachi network is created.
 * 4) The host installs and configures the Minecraft server software:   The server IP field in server.properties is left blank (as default).
 * 5) The host passes the newly created Hamachi network credentials to each of the players.
 * 6) The players connect to the host's Hamachi network.
 * 7) Now that all the machines are connected within the same Hamachi network, the host gives their machine's Hamachi IPv4 address to the players.
 * 8) Each player connects using this IP as per the usual Minecraft multiplayer screen.

Configuring the Minecraft server

 * 1) Configure the server by editing the server.properties file, the format for which is explained here. Be certain to edit the file with a text editor that does not add formatting (e.g., for italics), such as Windows Notepad. Additional configuration may not be necessary as many servers run fine from the default values.
 * 2) To become or add an operator (op), type  into the server console or gui. This adds the specified user's username and UUID to the   file. Operator status will not be changed if you change your username due to the use of UUID.
 * 3) * Administrators and operators may execute commands. In other words, operator (op) privileges allow you to control certain aspects of the game (e.g., teleporting players).
 * 4) If your server.properties is configured to enable whitelist, you can add a user to the  by typing  into the server console or gui. Due to the transition to the UUID system, it is not recommended to directly edit.

Connect to the Minecraft server

 * If you are playing on the same machine on which the server is running, select the "Multiplayer" option in the game client, click direct connect, and then type in "localhost" instead of an IP address.
 * Both hosting and playing on the same machine is not a recommended practice unless you have a powerful computer (e.g. more than 6 gigabytes of ram (5 for the server, 1 for the client, and remainder for system).
 * Users within your local network (i.e. that are accessing the same router) can connect using your internal IP address - port forwarding is not required for such local connections. The internal IP address of a specific network adapter can be found by typing "ipconfig" into command prompt and looking for the ipv4 address.
 * People connecting from the Internet (i.e., outside of your local network) must connect using your external IP address. You must port forward for someone outside your network to connect to the server.

IP address notes

 * Unless you set a static IP for the computer that is hosting the game, the internal IP address can change. This affects port forwarding rules, and can make them invalid. Each modem or router has a different way of setting a static IP address. You should refer to the manual for your device(s) or online documentation for further instruction.
 * If you are having players connect to your external IP, your external IP can change if you do not have a static IP from your internet service provider. Use a tool such as MyWANIP to periodically check on the external IP address. You may also search "my ip address" on Google and it will show your IP address. Alternatively, you can look into a DNS service that will allow you to have a name, rather than an IP address, that will remain the same. The name will point to your external IP address, regardless of whether or not it changes (the DNS is updated when changes occur).
 * For troubleshooting purposes you can try running Minecraft on the server machine and connect locally. You can connect trough either, your home network IP  or your public (Internet) IP.
 * If for some reason you have trouble with connecting publicly over your IPv4, try connecting over IPv6. This should only be done for testing whether your server is online, external players should still use IPv4.

Firewalling, NATs and external IP addresses

 * You must open the TCP port (default is 25565) on the firewall.
 * If the server in question is not reachable via a globally routable IP address, you will need to add appropriate address and/or port number translation rules to the gateway — usually your router has the global IP address.
 * For help with address translation, opening the firewall and routing (these three make up what people call port mapping/forwarding), portforward.com is a good source. Select your router from that list, skip the ad that comes after selecting the device, and you will see instructions for setting up port forwarding. Alternatively, you can read the documentation supplied with your router, modem, or other ISP related hardware.
 * Verify the port is open, and note your external IP by using a port checker tool, such as You Get Signal. The default port you should test is 25565, unless you specified something else. Have the Minecraft server running when you test the port.
 * You can obtain your external IP address from YouGetSignal.

Local network dedicated servers
This only applies to Classic (v0.30) servers.

A common problem for server administrators is the inability to connect to your own server via another machine on your local network. A typical scenario for this is that you have a Classic server running on a dedicated machine, and you have your own machine which you play on. They're both connected to the same router/switch, and have internal IP's with the octets '192.168.x.x'. Normally, connecting via the URL generated for your server will result in an error message claiming that the server is offline.

To correct this, you must add a function to the end of your URL, bookmarks, or whatever else you connect by. The function is: ?override=true Example: http://www.minecraft.net/classic/play/4c3bebb1a01816acbe31c5ece1570da5?override=true

Previously, (before the 1.8 beta and website update) this was &override=true. This caused much confusion since the change was not announced by Mojang, and wasn't announced on the website applet pages either. Before the update, connecting to your own URL via the website resulted in red text under the applet window saying "If you can't connect, try this link instead." The link returned the same thing, with the &override=true affixed to the end.

Note: This situation does not effect Beta servers, and you should be able to connect via an internal or external IP.

FAQ (frequently asked questions)
'''Q: I have a problem which is not answered in here! What should I do to?'''

A: Go to the Minecraft Forums and post your problem there. To help you, they need the following information: And please, if we were able to help you, post where the problem was exactly and what the fix was for that. Other people will appreciate that (and we will be able to get a grip on the common problems)!
 * Operating system
 * Version of Java
 * One machine or multiple computers
 * Exact description of the problem
 * Steps you have taken to solve the problem
 * Any errors you encountered
 * Screenshots of the problem (if possible)
 * Anything else that might help us to solve your problem - there almost never is too much information (passwords would be too much information!)

Q: On a Windows computer, when I double click the batch file it opens a command prompt window, but quickly disappears and the server does not start.

A: Right-click your .bat program and hit edit; add a new line and type  save and run the file. If it says invalid path, it is probably due to an incorrect path for javaw.exe or your server software. You may just need to change  to. Or search your system for javaw.exe and adjust the path accordingly. (It's probably under  or  .) Also, you must have the offline version of Java installed—not just the Java plug-in for your browser.

You can also try replacing the contents of the .bat file with: START "minecraft" "C:\Program Files (x86)\Java\jre7\bin\javaw.exe" -Xms1024m -Xmx1024m -jar "Minecraft_Server.jar" amending name values/locations as required

Q: Whenever I try to get the server up, it says "Failed to bind to port!".

A: This usually means that you have tried to use a port that is already in use or that you do not have permission to use (ports < 1024 are privileged and require root to bind to). You can try a different port by changing it in your  file in this line:.

Note: You should avoid using the following ports for your server as some ISPs may block these ports for security reasons and you shouldn't be running the Minecraft server as root (in the case of a Linux type OS and ports < 1024):
 * 21 (Used by most FTP Servers)
 * 22 (Used by Secure Shell daemon)
 * 25 (Used by Mail Servers for SMTP)
 * 53 (Used by DNS Servers)
 * 80 (Used by most Web Servers)
 * 110 (Used by most Mail Servers for POP3)
 * 115 (Used by Simple File Transfer Protocol)
 * 143 (Used by Mail Servers for IMAP)
 * 443 (SSL port for Web Servers)
 * 3306 (Used by most MySQL Servers)

Generally avoid any port below number 1024, since those ports are generally referred as well-known ports and are registered with the IANA for important services.

Q: I tried to run the server with Solaris/OpenSolaris and got the following error: java.io.InterruptedIOException: Operation interrupted at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:129) at java.net.SocketInputStream.read(SocketInputStream.java:182) at java.io.FilterInputStream.read(FilterInputStream.java:66) at gq.a(SourceFile:131) at ji.g(SourceFile:197) at ji.c(SourceFile:17) at oq.run(SourceFile:84) 2011-05-31 16:57:26 [INFO] /:44673 lost connection

A: For whatever reason, out of all of the operating systems, only Solaris throws that exception when a thread interrupts a connection. A workaround is to change the default behavior on the command line:

java -Xmx1G -Xms32M -XX:-UseVMInterruptibleIO -XX:+UseConcMarkSweepGC \ -XX:+CMSIncrementalPacing -XX:ParallelGCThreads=$CPU_COUNT -XX:+AggressiveOpts\ -jar minecraft.jar nogui

This instructs Java to use an interruptible IO stack instead of the default IO that is sensitive to interrupted threads.

Q: When I try to connect to my server this is what it says:  Connection lost The server responded with an invalid server key A: This error is usually caused when the server sends an unrecognized function to the client, which may be caused by using unrecognized server software, unbalanced client / server versions or modifications to the client.

Q: I cannot break/place any blocks!?

A: This is most usually caused by interacting with blocks in a protected area. If you are trying to interact near spawn, most likely it has been protected, by the minecraft server software; either build away from it or get operator status.

Q: My server runs fine but I cannot connect to it!

A: This could be caused by a series of issues. Please post a thread using the template provided above.

Q: How do you give a .jar server more ram?

A: Change the numbers in the server launch command "-Xmx1G -Xms1G". The -Xms part specifies how much memory the server starts with, and the -Xmx part is the maximum amount of memory the server can use. = 1GB = 2GB And so on.

Q: Why is the server CPU constantly at full load?

A: Some users are experiences full CPU load on the server. This may be caused by the GUI (graphic user interface) window. Run the server with the  option to disable this window.

'''Q: Help! How do you find out your server's IP address?'''

A: Read

Video/Alternative Tutorials
Here are some other tutorials on how to set up a Minecraft server:
 * Windows
 * Server Tutorial: How to Make A Vanilla Minecraft Server
 * How To Make a 1.6.2 Minecraft Server on Windows
 * How to Set Up and Host a Vanilla 1.5.2 Windows Minecraft Server
 * Mac OS X
 * How To Make a 1.6.2 Minecraft Server on Mac OS X
 * How to setup a 1.3.2+ Minecraft Server on OS X
 * Alternative video tutorial on setting up a Minecraft server with Mac OS X
 * Linux
 * Linux tutorial for more advanced users
 * How to Install Minecraft Server on CentOS
 * Others
 * How to Set Up Port Forwarding
 * How to Port Forward any Minecraft Server (1.6.2)
 * Alternative port forwarding tutorial for Windows (with pictures)
 * Full course
 * Course: How to Make a Server

Anleitungen/Server erstellen Tutoriels/Configurer un serveur 튜토리얼/서버 설치 Создание и настройка сервера 教程/架设服务器