Tutorials/Setting up a server

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

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 / Wi-Fi and especially WWAN / mobile data) is not recommended. Use a wired network instead, such as Ethernet. Satellite internet is also not recommended.
  • If you decide you don't want to host, but still want to play online, check out the public server options on a Minecraft server listing website.
  • 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 ensure it is always online for your players.

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

Warning

Template:Msgbox

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 can’t guarantee you'll be 100% out of danger.

In order to run your server and stay out of trouble, we highly suggest that 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 the Internet)

Some Security Information:

  • When you publicize your server make sure of:
    • Your server is not running on a super user(root(Linux))
    • Make sure that port 25, Port 465, port 587 is off(Mail port(Security risk/excessive background calculation risk))
    • Make sure that port 22 (Remote shell port) is on a whitelist with a SSH key(if you are even using this otherwise turn this off)
    • Make sure of your current Server type and version(update or skip vulnerable versions)
    • Check over your server plugins and mods for known vulnerabliities
    • Don't test plugins on the primary server instance
    • Make sure that the account does not have any root capabilities what so ever(exp: sudo)
  • Your ports should always be fire-walled to prevent intrusion
  • You should regularly make server backups
  • For personal servers:
    • Keep the server published only to a local host port

Java

Java is a programming language designed to create programs for the Java Virtual Machine (JVM). The JVM supports many different platforms. By doing this, developers write code for the JVM and any platform supported by the JVM can run the program. Further reading.(Remote shell port)

This section is designed to answer some frequently asked questions about Java and guide you through some decisions regarding Java.

OpenJDK vs OracleJDK

OpenJDK and OracleJDK are very similar. OpenJDK is the official open source reference implementation of Java. OpenJDK is an open source codebase that almost all other JDKs are built on. Excluding packaging, cosmetic and license differences OpenJDK is the same as OracleJDK.

Do note that OracleJDK (Oracle's "OTN") builds require a paid subscription for commercial and production purposes. This likely includes running a Minecraft server even if it is non-profit. Oracle does provide its own OpenJDK builds, but they are not packed into an installer format for easy use.

JRE vs JDK

JRE stand for Java Runtime Environment. JDK stands for Java Development Kit. JRE is a package tool designed to run Java programs. JDK is a package of tools designed to develop Java programs. The JDK comes with the JRE which comes with the JVM. If you have JDK then you have JRE and JVM. Vanilla Minecraft does not need JDK, but plugins may require it.

Headless Java

A headless Java installation is a trimmed down version of Java. It does not have a GUI or mouse/keyboard support. Headless Java is frequently used in Servers or other environments where a GUI is not needed. Template:Quote

Common instructions

The general gist of running a Minecraft server is that you will need to install java, run the server, accept the EULA, and run it again. Once you have installed java and opened up a command line, everything is basically the same.

  • Check the system requirements for CPU, RAM, and disk space.
  • Install Java. Use the OS-specific instructions below for this.
  • Download your server jar file from the download page.
  • Make a new folder for the jar file and move it there. This will be where all the configuration and the world files will be stored, so you don't want these to just sit in "Downloads".
  • Open a command prompt or a terminal interface. (On windows: search for cmd. On macOS: open terminal in launchpad."
  • Check again if Java is available. Type java -version.
  • Type cd (change directory), followed by the path to the folder where you placed your server jar file. You can drag the folder into the terminal window to get the path, if you have a GUI open.
  • Run the server for the first time by typing Template:Code (replacing the jar name (minecraft_server.jar in this case) by whatever you named the jar file to be).
  • A file called Template:Code will be generated after you run the server for the first time. Open it in a text editor and change eula=false to eula=true. 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.
  • Now the server has been set up, and you can simply run it with Template:Code. If you don't want a GUI for typing commands, add a space and Template:Code to the command. (Some people say it makes the server much much faster.) You can also use a few other switches described below.

At this point you should have a basic server running. See Configuring the environment for more information about configuring your server. One of the things you definitely want to do is writing a script to launch the server so you don't have to remember the command line.

Java options

Java options should be added between the Template:Code and the Template:Code on the command line, or in your startup script.

Memory limits
The most important thing for a Minecraft server is memory to run with. -Xmx defines how much memory it is allowed to use. Template:Code (2 gigabytes) is more than enough for a home server with 5 players on default simulation distance (5×212 = 2205 chunks simulated), but do scale it up by your actual settings. Setting the value too low causes frequent GC stops. Making it too high can make GC too long on Java 8 – a version you should not be using in the first place.
Template:Code (the initial memory size) is the next biggest knob, but only affects startup performance. If your server also runs things other than Minecraft, set it to 1/4 of the maximum size (so for our case, Template:Code) for a good balance: the JVM will be allowed to return some memory to the OS when it's not needed. (The return algorithm is very conservative, so it has very minimal effect on long-term performance.) If your server is fully dedicated to Minecraft, feel free to go higher: making it equal to the maximum size disables heap scaling and gives maximum startup speed.
A "soft max heap size" (Template:Code) is available for some versions of JRE. The JRE will try to only use that much memory, but will go over to a maximum of -Xmx if necessary. If you are running many things on your server, this may be useful.
GC
The default GC on Java 9+ used by modern Minecraft is G1GC (Java 8 also has it, but it is off by default). The flags used by the official launcher Template:Code works reasonably well, though of course better flags (brucethemoose) exist. (Aikar's famous flags are good, but not optimal.)
On Java 14+, ZGC is available. This GC is almost lag-free with millisecond-level pauses. Delete all GC-related flags and simply use Template:Code. Tuning flags other than Template:Code are a lot less important compared to in GCs (the default is quite good), although Template:Code is worth a try if you want to trade memory for lag.
VM
On Solaris, use -d64 to tell the JVM to use your 64-bit processor properly. Since nobody uses Solaris, this is irrelevant.
Calculations may be made faster with GraalVM, benefiting operations such as chunk generation. A basic version is bundled in the common "HotSpot" Java 9–15, but it was later removed due to maintenance burden. Now you need to download it separately: use instructions from brucethemoose.

To sum up, a reasonable flag combination can be as simple as Template:Code. That is it. There are bits that you can squeeze from complicated flags, but you would get much more from modified server software. In fact, all serious discussions (e.g. Aikar and brucethemoose) of server performance assume some degree of modding.

Minecraft options

Options for the server JAR go after the Template:Code part. Run with --help to see all available arguments that can be passed to the server. Below is a list of available commandline options for the server.

--bonusChest
If a bonus chest should be generated, when the world is first generated.
--demo
If the server is in demo mode. (Shows the players a demo pop-up, and players cannot break or place blocks or eat if the demo time has expired)
Equivalent to playing Minecraft without a account, you have about 5 in-game days before your trial ends.
--eraseCache
Erases the lighting caches, etc. Same option as when optimizing single player worlds.
--forceUpgrade
Forces upgrade on all the chunks, such that the data version of all chunks matches the current server version (same as with sp worlds).
This option significantly increases the time needed to start the server.
--help
Shows this help.
--initSettings
Loads the settings from 'server.properties' and 'eula.txt', then quits.
--jfrprofile
Initializes the Java Flight Recorder on the server. Only available on 1.18+.
--nogui
Doesn't open the GUI when launching the server.
You will still be able to interact with your server, but you must use the cmd or Terminal if enabled.
  • nogui does the same thing as this option for backward compatibility with very old versions of the server, but --nogui is preferable as it matches the format of other options
--safeMode
Loads level with vanilla datapack only.
--serverId <String>
Gives an ID to the server. (??)
Used only in crash reports. If not given, then the "Server Id" detail is not added to crash reports.
--singleplayer <String>
Runs the server in singleplayer mode. <String> is the name of the Singleplayer player.
The Singleplayer player data is loaded from Player in the level.dat file.
Monsters spawn ignoring the 'spawn-monsters' property unless the difficulty is Peaceful. Animals spawn ignoring the 'spawn-animals' property.
The default permission level is 0 (ignoring the 'op-permission-level' property) unless otherwise specified for a player in ops file.
The permission level required for the Template:Cmd command is 4. Although the server is already published.
The permission level required for the Template:Cmd command is 0, not 2.
Blacklists are disabled. These commands are not available: Template:Cmd, Template:Cmd, Template:Cmd, Template:Cmd, Template:Cmd.
The local IP is '127.0.0.1' ignoring the 'server-ip' property. Use of authentication is disabled ignoring the 'online-mode' property. Prevention of proxy connections is disabled ignoring the 'prevent-proxy-connections' property.
The default game mode (the 'gamemode' property) is still used for new players, but does not change the world's default game mode (GameType in the level.dat file).
--universe <String>
The folder in which to look for world folders. (default: Template:Code, the current directory)

The following options are available from server.properties too. It might be a better idea to edit that file instead for easier management:

--world <String>
The name of the world folder in which the level.dat resides. (default: Template:Code)
This is the same as Template:Code.
--port <Integer>
Which port to listen on, overrides the server.properties value. (default: -1, read from server.properties)
See Server.properties, option "server-port", for restrictions on this value.

Example command line

  • Running a world found in the folder "cold" on port 1337, with 1G of RAM allowed: java -Xmx1G -jar minecraft_server.jar --port 1337 --nogui --world cold.

Windows instructions

Installing Java

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 and Firefox browsers do not run Java content and therefore cannot check Java through the browser.
  • Open a command window and enter the command java -version. 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 the newest version at https://adoptopenjdk.net/ (OpenJDK) or http://www.java.com/download/ (Oracle "OTN" JDK)

macOS instructions

Keep in mind that the server won't run correctly on macOS 10.4 and earlier and may crash your machine.

Installing Java

Open the terminal.

  • Check if you have java by running java -version. Make sure it's newer than 1.6 (best if newer than 1.8), for most versions, or java 17+ on 1.17 & 1.18.

Setting up the Minecraft server

See the Common instructions.

Using Time Capsule

Template:Msgbox 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.

  • 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.

That's it! You're now ready to configure your server.

Linux instructions

Linux comes in many different varieties called distributions (distros). Some of these distros are designed or better suited for running a server. If you are setting up a dedicated server it is recommended to use one of these distros.

Linux, in general, is more welcoming to open source programs. So where applicable it is recommended you use open source programs, such as OpenJDK.

Installing Java

For most distributions, it is recommended to install OpenJDK 16 (for 1.17+) or OpenJDK 8 (for below 1.17) from the official repositories. For Oracle Java refer to Oracle's Download Page.

Note: While not affecting Minecraft server, JavaFX or other proprietary aspects of Java will need to be installed separately.

Specific instructions are included for each distro below, but not all have been updated to 1.17. If it only says to install OpenJDK 8, that means that it has not yet been updated to 1.17.

Solus

Run sudo eopkg install openjdk-8 to install OpenJDK.

For OracleJDK refer to Solus Help Center

Note: OpenJDK 11 is not in Solus' repositories.

Debian, Ubuntu, Raspbian

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

Due to licensing issues, the repository frequently used to install Oracle Java has been discontinued. It is now recommended that you install OpenJDK 8 or above.

OpenJDK can be installed with one command:

  • sudo apt update; sudo apt-get install openjdk-8-jdk-headless below Minecraft Server 1.17
  • sudo apt update; sudo apt install openjdk-16-jdk-headless at or above Minecraft Server 1.17

Removing the 'headless' part of the command will install all components of Java.

Note: <1.17 tested in Ubuntu 18.04, 1.17 tested in Ubuntu Server 20.04.2 LTS

openSUSE

Note: Due to possible instability openSuse Tumbleweed is not recommended as a dedicated server.

Just run the command from the terminal: sudo zypper in java-1_8_0-openjdk

Java should be installed.

Note: Tested in openSuse Leap 15.1

Arch Linux

Both java 8 and 16 are in arch linux's repostiory.

Just run pacman -S jre-openjdk-headless, For the OpenJDK 16 JRE, Remove "-headless" for the full JRE if you want to run with GUI.

Just run pacman -S jre8-openjdk-headless, For the OpenJDK 8 JRE, Remove "-headless" for the full JRE if you want to run with GUI.

If you encounter issues it is recommended that you refer to the ArchWiki

Gentoo

Run emerge --ask virtual/jdk

Gentoo Wiki

Other distros

Check your distro's documentation. It should have information on how to install OpenJDK.

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.

File:RunMinecraftServer.png

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

Template:Update 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 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: <syntaxhighlight lang="sh"> kldload linprocfs mount -t linprocfs linprocfs /compat/linux/proc </syntaxhighlight> and add this line to /etc/fstab: 

linprocfs   /compat/linux/proc   linprocfs   rw   0  0

The Oracle JRE has a dependency marked as forbidden and the installation will fail. Go to /usr/ports/textproc/linux-f10-expat2.0.1/ and in the Makefile remove the line which starts with FORBIDDEN=.

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 /usr/ports/distfiles. Then to install the JRE, go to /usr/ports/java/linux-sun-jre17/ and run make install distclean.

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 java -version. You may end up with a message that it cannot find libjli.so. One way to fix it is to add your java paths to the search explicitly. Make a symlink: <syntaxhighlight lang="sh"> ln -s /usr/local/linux-sun-jre1.7.0/lib/i386 /compat/linux/usr/lib/java </syntaxhighlight> And in /compat/linux/etc/ld.so.conf.d/java.conf add: 

/usr/lib/java
/usr/lib/java/jli

Run /compat/linux/sbin/ldconfig. Now java -version 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 syscall epoll_create not implemented if you run the server in the usual way, so we add this line to the command to fix that -Djava.nio.channels.spi.SelectorProvider=sun.nio.ch.PollSelectorProvider.
The command to launch is like: <syntaxhighlight lang="sh"> java -Xmx1024M -Xms1024M -Djava.nio.channels.spi.SelectorProvider=sun.nio.ch.PollSelectorProvider -jar minecraft_server.1.7.10.jar --nogui </syntaxhighlight>

Plan 9

alien-convert PATH_TO_YOUR_JRE.deb
chmod ~/~ rwx # for current user
snarf java -jar PATH_TO_SERVER_JAR.jar xvmf in acme

Place Holders have been used in this example shell script including PATH_TO_YOUR_JRE.deb and PATH_TO_SERVER_JAR.jar replace them with /INSERTACCOUNTREGISTERNAME/.../INSERTJRENAME.deb and /INSERTACCOUNTREGISTERNAME/.../INSERTJARNAME.jar

Hostman

Hostman is an application hosting provider to host apps in the cloud. Minecraft is available as a one-click app package on Hostman. Installation takes about 2 minutes, there's an instruction on how to configure the server and start playing. You can have multiple Minecraft services on one server. Try a free demo here.

Cloudron

Cloudron is a platform to self-host apps on your server. Minecraft is available as a one click app on Cloudron. It comes with a web interface to manage Minecraft from the browser. You can also have multiple installations of Minecraft on the same server. You can try a demo here (username: cloudron password: cloudron)

Docker

Docker is a free container based platform which helps to isolate instances of a Minecraft Server from each-other and from the host system. Docker and the owner of the repository of the container are not affiliated with Mojang.

Getting docker (for Linux, Mac & Windows)

Read https://docs.docker.com/install/

Docker image

  1. Download the image by running <syntaxhighlight lang="sh" inline>docker pull sirplexus/minecraft-server-standalone:latest</syntaxhighlight>
  2. Set up the container with port 25565 open, 1G ram assigned and named "MyServer": <syntaxhighlight lang="sh" inline="">docker container create --publish 25565:25565/tcp --name "MyServer" --env RAM=1G sirplexus/minecraft-server-standalone</syntaxhighlight>
  3. Start the container: <syntaxhighlight lang="sh" inline>docker container start MyServer</syntaxhighlight>

Updating Docker image

For updating minecraft-server-standalone run <syntaxhighlight lang="sh"> docker pull sirplexus/minecraft-server-standalone:latest </syntaxhighlight>

Docker-Minecraft on Synology diskstation

NOTE: This is for self-hosted worlds NOT a standalone. You will need to download a server.jar for the official site.

Docker is an "Add-on Packages" on many new Synology Diskstations, and many of them are powerful enough to run at least one Docker Minecraft.

Before starting the docker, you need to make a folder containing the version of Minecraft you would like to play (It has to be named "server.jar") and an eula.txt (read about this under "Common instructions").

The way to setup a Minecraft server on a Synology Diskstation is to:

  1. Install and open docker on your Diskstation
  2. Search for "sirplexus" under Registry and find "sirplexus/minecraft-server". Right click and "Download this image".
  3. After download you can find the image under image. Press "Laungh"
  4. Press "Advanced settings" and go to the tab "Volume". Add the previus created folder and set "mound path" to "/srv/minecraft".
  5. Go to the tab "Port Settings" and assign a "Local Port". This is the port you will connect to from the Minecraft Launcher.
  6. Press "Apply" and "Next" and again "Apply" to finish the container.

You will now be able to play Minecraft on your Synology Diskstation. The IP address it the IP of the Diskstation and the Port number is assigned undet step 5.

Configuring the environment

Writing a script to launch the server

It's definitely boring to have to remember the command-line options for your server every time you launch it. Luckily, we can write it down in a file and just run that instead.

On Windows

The windows version of a script is called a batch file. Create a text file in the folder where you put the jar as "start.bat", and then right click it to edit using notepad. Paste the following in:

<syntaxhighlight lang="bat"> @ECHO OFF java -Xms1024M -Xmx2048M -jar minecraft_server.jar --nogui pause </syntaxhighlight>

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.

The "pause" command is there to keep the window open so you can read what happened after the server stops.

On macOS, Linux, and FreeBSD

All these systems use a common scripting language called the "POSIX shell script" on the command line. Create a text file in the folder where you put the jar as "start.sh" and write the following in:

<syntaxhighlight lang="sh">

  1. !/bin/sh

cd "$(dirname "$0")" exec java -Xms1G -Xmx1G -jar server.jar --nogui </syntaxhighlight>

Now save the file. Run Template:Code (or path to wherever you put the script) to make it executable. You can now run the file by double-clicking or by running Template:Code in the folder (or using a whole path from outside there).

If you want to add a pausing part like the Windows example, remove the Template:Code word, and add a line of Template:Code to the end. This is useful if you are running the script by double-clicking on the GUI.

On Plan 9

(I don't use Plan 9, so I have absolutely no idea how to use the rc, psh, acme, snarf magic. Someone please add it.)

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:

Port forwarding

Template:See also 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.

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". If "TCP/UDP" or "Both" isn't an option you will have to create two rules for both protocols. 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:

Template:OS Windows
Press Template:Key; this should be up to the "Run" dialog box. Type Template:Kbd and hit Template:Key. This should open a command window with a black background. From there, type Template:Kbd and press Template:Key. 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 parentheses or letters.
File:Ip-address-mac-610x206.jpg
The IP location on OS X
Template:OSMac
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.
Template:OSLinux
Either you use the network diagnose center (depending on distribution), or the terminal with ifconfig. The output should return all your interfaces. Search for inet addr:xxx.xxx.xxx.xxx, 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

Now it is time to configure and connect.

Setting up a VPN

Template:MsgboxTemplate:Disclaimer

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 who 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 is Hamachi by LogMeIn. OpenVPN is another (free, open source) alternative that supports most OSes, but is a bit more difficult to configure. Free Radmin VPN is another software with no need to register on the website and no limits per the number of users. 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 .deb and .rpm 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.
  9. Note that Hamachi has been squatting on an IANA-allocated IP block (25.0.0.0/8). As such, Hamachi fundamentally conflicts with the internet itself.

Setting up Radmin VPN

It is very similar to Hamachi installation.

  1. Download free and install Radmin VPN
  2. Create a network: after Radmin VPN installation on the local computer press "Create network" button. Set a Network name and a Password —> Press "Create" button.
  3. Now the new network will appear in the main window —> invite friends, send them the info to connect -> you are welcome to run Minecraft.
  4. Connection: after program launch press “Join network" —> in the dialog box press enter Network name and Password received from the network administrator —> "Join" —> the new network and its nodes will be shown in the main window. —> Connect to the host in Minecraft.
  • If the connection on Radmin VPN has been established, but you don`t see other players in the game, then it is required to adjust firewall for work of the game or just turn the firewall off.

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 Template:Cmd into the server console or gui. This adds the specified user's username and UUID to the ops.json file. Operator status will not be changed if you change your username due to the use of UUID.
    • 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).
    • ops.json contents:<syntaxhighlight lang="json">

[ 

 {
   "uuid": "",
   "name": "",
   "level": 4,
   "bypassesPlayerLimit": false
 }

]</syntaxhighlight>

  1. If your server.properties is configured to enable whitelist, you can add a user to the whitelist.json by typing Template:Cmd into the server console or gui. Due to the transition to the UUID system, it is not recommended to directly edit whitelist.json.

Connecting to the Minecraft server

Template:Msgbox

  • 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 Template:Cd 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 (4 for the server, 2 for the client, and some for the rest of the 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 the command prompt and looking for the IPv4 address, or by using this website. If the port is set to a number other than 25565 in server.properties, that port must be included. This address (both IP and port) will look something like Template:Cd.
  • Users 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 WanIP 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 DDNS 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, hence "dynamic").
  • For troubleshooting purposes you can try running Minecraft on the server machine and connect locally. You can connect through either localhost, your home network IP (192.168.x.x) 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 a TCP/UDP 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.

The SRV record

Java Edition since 1.3 also supports using custom ports without requiring the player to type it. This is achieved by using a SRV record (for "service") in the DNS. The SRV record tells Minecraft the actual host and port to use; some DynDNS services and most static DNS services allow you to set it up.<ref>https://www.noip.com/support/knowledgebase/how-to-add-a-srv-record-to-your-minecraft-server-remove-the-port-on-the-end-of-the-url/</ref>

To manually verify the SRV record, use (assuming the player-facing domain is "YOUR.DOMAIN.com"): 

> nslookup -q=srv _minecraft._tcp.YOUR.DOMAIN.com
Server:  UnKnown
Address:  [REDACTED]

Non-authoritative answer:
_minecraft._tcp.YOUR.DOMAIN.com  SRV service location:
          priority       = 5
          weight         = 5
          port           = 65312
          svr hostname   = ACTUAL.DOMAIN.com

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:

  • 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!)

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)!

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 pause save and run the file. If it says invalid path, it is probably due to an incorrect path to java.exe/javaw.exe or your Minecraft server jar file. You may just need to change /jre7/ to /jre6/ . Or search your system for java.exe/javaw.exe and adjust the path accordingly. (It's probably under c:\program files or c:\program files (x86).) Also, you must have the offline version of Java installed—not just the Java plug-in for your browser.

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

A: The most common reason this happens is because you put an IP address in the server-ip field in your server.properties file. If the IP you specify isn't the same as any of your network interfaces, (your wireless or wired IPv4 from ipconfig/ifconfig/ip a) Minecraft will throw the port binding failure message. By leaving it blank, you let it bind to all interfaces. You will then be able to connect using localhost and people on your wired/wireless network (in the same subnet) can connect using the computers/server's (private) IP address.

Alternatively, the error can mean 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/Administrator access to bind to). You can try a different port by changing it in your server.properties file in this line: server-port=25565.

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. -Xmx1G -Xms2G = 1GB -Xmx2G -Xms1G = 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 --nogui option to disable this window.

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

A: Read #Connecting to the Minecraft server

Q: I port forwarded and allowed java.exe in my firewall and it's still not working!

A: Your modem might be acting as a router as well. If you switch ISP's or upgrade your connection to the Internet, you may get issued a modem/router combination (which might explain why it worked in the past). You can verify this by looking for the WAN IP of your router. If it's a private IP, you'll need to log into the modem/router your ISP issued to you, and configure port forwarding to the WAN IP of your router.

Q: I turned off my firewall on my router/modem how does it still not work???!!! However, port forwarding sites report they can "see" me?? What's going on???!!

A: Turning off your firewall on your router/modem means you essentially disabled port forwarding. Port forwarding is actually a subset of firewall rules. If no rule exists on that port (for example 25565), the firewall will ignore/drop the connection attempt (hence, you get a connection timed out). If there is a rule, it should pass on the connection to whatever computer is configured to receive the initial connection attempt.

When you disable the router/modem firewall and test your public (non RFC 1918) IP address on a port forwarding-checking website, the website will hit your router/modem, and your router/modem will respond, yes you can see me. This is another reason why disabling your firewall is bad; you incorrectly believe that people outside your network can connect to your Minecraft Server on your computer, when really, they're trying to connect to the router/modem itself.

To solve this, the next step is to confirm if your port forwarding (rules) are correct. By Google-ing "minecraft server checker" you'll be able to check if you configured your network correctly such that users outside your network running the Minecraft client can indeed connect to your computer through your router/modem.

Note: You may need to be careful about the Minecraft Query - It may use layer 4, the transport layer - UDP to query your server. Many Internet and Youtube guides will only tell you to port forward TCP (this guide outlines that you do both).

Q: What is connection timed out and connection refused?

A: Simply put, connection timed out is when a firewall ignores a connection attempt (ignores the intial connection packet with the SYN flag in the 3-way handshake). Connection refused is when there's no process listening on the port; therefore, the operating system lets the client (in the standard client-server model) know their connection attempt did not work.

The default configuration on all Windows computers (the home version) and (just about) all (SOHO) routers is to drop or time out the connections. This is called "stealth mode" and you can read more about it on superuser. Here's a brief summary: "The idea is that refusing a connection instead of timing it out will tell an attacker that there actually is a computer on that IP-Address. With the connection attempt timing out, the hope is that the attacker will ignore the computer."

You can read more about connection refused on serverfault.

So if your error message is a connection timed out, it's usually a firewall problem - you either need to allow Java in the Windows firewall or port forward. If the error message is a connection refused, perhaps your Minecraft server has not started properly or you turned off the firewall on your router instead of port forwarding.

As always, you can always ask the Minecraft Forum if you are uneasy or unsure about something, particularly if opening the command prompt/terminal and running commands makes you nervous.

Connection filtered and connection closed is another way of saying timed out and refused, respectively.

Video/Alternative Tutorials

Here are some other tutorials on how to set up a Minecraft server:


<references/>

Template:Tutorials

de:Anleitungen/Server erstellen es:Tutoriales/Configuración de un servidor fr:Tutoriels/Configurer un serveur ja:チュートリアル/サーバーのセットアップ ko:튜토리얼/서버 설치 ru:Создание и настройка сервера zh:教程/架设服务器

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