Minecraft Guides
Set up a Java or Bedrock server, fix connection errors, and improve Minecraft server performance.
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Connection and login errors
How to fix the Minecraft getsockopt error
The getsockopt message alone does not tell you at what stage the connection was lost. Read the entire statement on the screen. Connection refused and Connection timed out require different controls.
How to fix “Connection timed out” in Minecraft
A timeout indicates that the client did not receive the expected response within the time limit. A closed server, wrong port, or network rules that silently drop packets can lead to the same result.
How to fix “Connection refused” in Minecraft
If the connection is rejected, the first thing to check is whether the correct service is listening on the destination port. The wrong port, an incomplete server, and a network rule that explicitly rejects it can produce this symptom.
How to fix “Unknown host” in Minecraft
Unknown host indicates that the typed name cannot be resolved. Check the spelling of the address and the DNS result before assuming the server may be down.
How to fix “Outdated client” in Minecraft
The server considers the protocol used by the client to be outdated. Instead of randomly switching the client to the latest version, find out which version the server accepts.
How to fix “Outdated server” in Minecraft
Your client may be using a newer protocol than the server accepts. The solution is to select compatible client as player or schedule server upgrade as administrator.
How to fix “Invalid session” in Minecraft
Invalid session often requires refreshing the Launcher session. First check the player session without changing the server's authentication settings.
How to enter Minecraft Java and Bedrock server?
Java and Bedrock are different clients. First find out which edition the server accepts, then the address and port if necessary.
How to turn on Minecraft multiplayer if it is turned off?
If the Multiplayer button is grayed out due to account settings, check your Microsoft account permissions first. In the family account, the authorized adult changes the setting.
How to check whether a Minecraft server is online
Minecraft status query with address and edition shows whether the server responds to the listing protocol. Look at the time of the query as well as the result.
Networking, DNS and ports
How to create SRV record for Minecraft Java?
SRV record allows Java players to connect to private port without typing port. In the example, the player uses play.example.net and the server uses node.example.net:25566.
How to connect a domain name to a Minecraft server?
To use a custom domain name, resolve the game address to the server's public IP. You can keep the website address and game address in different subdomains.
How to set a Minecraft DNS record to DNS only in Cloudflare
Cloudflare's standard web proxy is not designed to transfer gaming port like regular HTTP traffic. Use the game save as DNS only on a separate subdomain.
How to do port forwarding from modem for Minecraft server?
To make the home server accessible from the internet, the modem must route the correct gaming protocol to the server computer. First verify that the server is running on the local network.
How to open a Minecraft server behind CGNAT?
If you have CGNAT, the port forwarding on your home modem cannot deliver the connection from the provider's upper network to you on its own. First check your modem's WAN address.
What ports do Minecraft Java and Bedrock use?
The default Java gaming port is 25565 TCP, the classic Bedrock IPv4 port is 19132 UDP. The configuration of the server and the transport format used may change these values.
How to check if Minecraft Java TCP port is open?
Distinguish between three separate results when testing the Java port. There may be a process listening on the port, TCP may be accessible from the outside, and the Minecraft protocol may respond.
How to test Minecraft Bedrock UDP port?
Instead of looking at a random TCP port site for Bedrock, use a Bedrock status request tool or an actual Bedrock client.
When does Minecraft DNS record work when updated?
The reason why the new address works on some players but not on others may be due to the old DNS result remaining in the cache. First compare the authorized record and the externally visible record.
Minecraft server is running on home network but my friends can't log in
Login from the local network indicates that the server software is running. In an external connection, the game package must also reach the server from the modem.
Server setup
How to set up a Minecraft Paper server?
To install Paper, first determine the Java version that the target Minecraft version requires. Running the server in a separate directory makes it easier to manage files and backups.
How to set up a Minecraft Java Vanilla server?
Vanilla is Mojang's Java Edition server software. You can run it in your own folder for a friend server that is plug-in-free and close to the official game.
How to install Minecraft Bedrock Dedicated Server?
Bedrock Dedicated Server is separate server software for Bedrock clients. If players are using Java Edition, you need to make a connection plan separately.
How to open a Minecraft server in Aternos?
In the Aternos panel, first select the edition and software. Using the same Minecraft version as your friends avoids the most common incompatibility on first connection.
What is Aternos DynIP and how to use it?
DynIP is the temporary address that Aternos shows on the connection screen for Java Edition. Used for comparison when resolution of the normal address fails.
How to choose the right Java version for Minecraft server?
Java requirements are determined by the version of Minecraft you use, as well as the version of Paper, mod loader, or proxy you use. Check the documentation for each component before installation.
How to solve Minecraft UnsupportedClassVersionError?
This error indicates that the Java running is too old for the server or plugin class it is trying to load. Find out which component the class in the first error comes from.
How to solve Minecraft eula.txt error?
The Java server does not complete the boot without accepting the EULA terms. Check that the file is organized in the correct server folder.
How to prepare start.bat or start.sh for Minecraft server?
The initialization file ensures that you use the same jar file, Java path, and memory settings every time you boot. Keep file format separate for Windows and Linux.
How to fix “Failed to bind to port” on a Minecraft server
If the server cannot connect the port when it starts up, another process may be listening on that port or an IP that does not belong to the machine may have been written in the configuration.
Server configuration
How to edit Minecraft server.properties?
In the Java server, basic options such as port, game mode and whitelist are in the server.properties file. Before editing, shut down the server properly and make a copy of the file.
How to open whitelist on Minecraft Java server?
Whitelist limits the server's player access to accounts you allow. Add your own account first, then enable the list and try with two different accounts.
How to open allowlist on Bedrock server?
Bedrock Dedicated Server uses the allow-list setting for accepting players. Define the allowed user with the Bedrock gamertag.
How to grant or revoke OP on a Minecraft server
OP grants broad management authority. To delegate, you'll need access to the server console or an already authorized administrator account.
How to change game mode on Minecraft server?
Changing the default game mode and changing a specific player's game mode are separate operations. Determine the scope you want.
How to change difficulty on Minecraft server?
You can change the world difficulty on the Java server with a command, and check the setting at startup via server.properties.
How to enable keepInventory on a Minecraft server
Change the relevant world's inventory protection rule so that players retain their items upon death. The command name may look different depending on the Minecraft version.
How to configure Minecraft spawn protection
If the blocks in the spawn area cannot be broken for normal players only, check the vanilla spawn protection. Zone protection plugins can also cause the same symptom.
How to change player limit on Minecraft server?
The player limit can be configured directly, but it is necessary to measure the capacity that the machine can handle. The proxy and the back server can impose separate limits at the same time.
What does the Minecraft online-mode setting do?
In Java, online-mode controls whether the server verifies the player account online. Keep default validation on a normal Java server directly exposed to the internet.
Java, Bedrock and proxies
What is the difference between Minecraft Java and Bedrock?
Java and Bedrock use different client and server protocols. Before sharing a server address, determine which edition is supported.
How to install Geyser on Paper server?
Geyser is a bridge that allows Bedrock players to connect to a compatible Java server. Use the platform-appropriate Geyser version on Paper.
What does Minecraft Floodgate do and how to install it?
Floodgate provides a separate authentication flow for login with a Bedrock account on a Java server using Geyser. First verify that Geyser is working.
Why can’t Bedrock players connect through Geyser?
If Java players can log in and Bedrock players cannot, first distinguish between the Geyser listener, the correct Bedrock port, and client compatibility.
How to install Minecraft Velocity proxy?
Velocity allows players to switch to multiple Java servers from a single address. Proxy and backend servers use separate processes and ports.
How to configure modern forwarding in Velocity
Modern forwarding ensures that information such as player IP and UUID are verified and transferred from Velocity to Paper. The settings of the proxy and all backend servers must match.
How to solve Velocity server cannot connect to lobby error?
If there is a connection to the proxy but the lobby does not open, the problem starts after the path between the client and the proxy. Compare Velocity and backserver logs at the same timestamp.
How to install ViaVersion and what versions does it support?
ViaVersion allows the newer Java clients it supports to talk to the legacy server protocol. Verify target client and server versions against the support table before installing.
What is the difference between ViaVersion and ViaBackwards?
ViaVersion and ViaBackwards serve different aspects of connectivity. Determine first whether the client version is newer or older than the server.
How to check mod compatibility on Fabric, Forge and NeoForge servers?
The same Minecraft version alone is not enough to log into the modded server. The mod installer, mod versions and dependencies must also be compatible.
Performance and lag
How to diagnose lag on Minecraft server?
High ping of the player, low FPS on the client and long tick time on the server are separate problems. First find out which metric is changing with the problem.
What do Minecraft TPS and MSPT mean?
TPS indicates the number of ticks processed by the server per second. MSPT measures how long a tick lasts. A target of 20 TPS has a budget of approximately 50 ms per tick.
How to profile a Minecraft server with spark
spark lets you see where the game server is spending processor time. If you get the report while the problem is occurring, your chances of getting the right job increase.
How much RAM should be given to the Minecraft server?
The number of players alone does not tell you the correct amount of RAM. World, modpack and addons change memory consumption. Make the decision based on the measured load.
What is the difference between Minecraft view distance and simulation distance?
View distance affects the area sent to the player, and simulation distance affects the area actively rendered around the player. Test both separately.
How to pre-create a Minecraft world with Chunky?
World pre-generation moves some of the chunk generation load that occurs when players explore to maintenance time. Calculate disk cost from the beginning.
What “Can’t keep up!” means in a Minecraft server log
This warning tells you that the server is behind schedule. It is not possible to understand which plugin or setting is responsible with a single line.
How to solve OutOfMemoryError on Minecraft server?
Start by reading the OutOfMemoryError type. Java heap fullness, local memory issue, and process terminating from hosting limit are not resolved in the same way.
How to diagnose lag from mobs and farms in Minecraft
Heavy mobs, hopper chains and redstone machines can create tick load. First determine which world and region your burden is concentrated in.
What to do if Minecraft ping is high but TPS is normal?
High ping may occur when the server is running at normal tick speed. Compare the player's network path with the externally observed response of the server to understand the problem.
Plugins and mods
How to install plugin on Minecraft Paper server?
A Paper addon must be compatible with your versions of Minecraft, Java and server software. Read the dependencies on the distribution page before installing the file.
Minecraft plugin is not loading or not working, what to do?
The reason why the plugin is not working usually appears in the startup log. Find the first load error with the relevant plugin, not the last chain error.
How to solve Minecraft UnknownDependencyException?
UnknownDependencyException indicates that another plugin required for a plugin to work is not found or loaded. Follow the dependency name in the error message.
How to update Minecraft plugins safely?
In addition to jar changes, a plugin update can also make data or configuration changes. First save the old version and its data for rollback.
How to authorize a Minecraft group with LuckPerms?
In LuckPerms, instead of giving the player many powers directly, you can create a group appropriate to your task. First find out which permission node is required for which command.
How to find LuckPerms permission not working error?
If a player doesn't have command authority, first see which permission node the plugin is actually asking for. The visible command name and the permission node do not have to be the same.
How to set up a Minecraft mod pack server?
When running a modpack on a server, use your own server distribution if you have the package. Not every mod in the player package may be suitable for the server side.
How to resolve registry or mod conflict on modded Minecraft server?
A missing record or mod channel error on input may indicate that the client and server are not loading the same list of content.
How to install datapack on Minecraft server?
Datapack adds data-driven content to the vanilla world. Place the file in the correct world's datapacks directory and check compatibility with the game version.
WorldEdit vs. WorldGuard and how to protect your spawn
WorldEdit is used for block editing and region selection, and WorldGuard is used to enforce game rules in regions. The two have separate roles in spawn protection.
Worlds and backups
How to take a full backup of Minecraft server?
A restoreable backup requires configuration, player permissions, and plugin data as well as world folders. Copying random files from the running server may create inconsistent backups.
How to restore Minecraft server from backup?
Verify the restore in a separate directory first. This way, if the wrong date or missing file is noticed, you won't crush the current world.
How to transfer Minecraft single player world to server?
To move the Java single-player world to the Java server, copy the world folder as is. Bedrock worlds use a separate save format.
How to upload a Minecraft world to Aternos?
Check edition and version compatibility before uploading the world. Preserve the option to return by downloading the current Aternos world separately.
How to create a world with a new seed on the Minecraft server?
Seed is the input of world production. Instead of preserving the existing structures and turning the entire world into a new seed, create a new world folder.
How to set worldborder on Minecraft server?
Worldborder limits the area players can access. The number given in the java command is the width instead of the radius.
How to find and backup Minecraft Nether and End folders?
The location of the Nether and End folders varies depending on the Java version and server software. Don't assume the old directory layout when moving from one version to another.
How to upgrade Minecraft Paper edition without breaking the world?
Try the upgrade on a copy of the world first. It may not be safe to just revert to the old jar file after the world format has been upgraded.
What to do if the world does not open or is corrupted on the Minecraft server?
If there is a world error at startup, first protect the data and find out which file or region the error occurs in. Don't keep rebooting on the problematic world.
How to move Minecraft server to new host?
When moving a server, world files, plugin data, and network settings change together. Test the new environment before changing the player address.
Security and administration
How to ban and remove ban on Minecraft server?
Banning by name on the Java server blocks the specific player from entering. IP ban may also affect other people using the same network, verify the target player first.
How to roll back griefing with CoreProtect
CoreProtect can undo previously saved block changes. Narrow the player, time and space limit before starting a large operation.
How to enable Paper Anti-Xray
Anti-Xray changes the block information sent to the client, reducing the ease with which gems are visible. Verify settings based on Paper version and world.
What is Minecraft RCON and how to use it safely?
RCON runs a remote console command. So instead of making access public in the same way as the game port, restrict it to the management network.
How to secure Paper backends behind Velocity
Direct access to the Arka Paper server may allow players to bypass checks in the proxy. Restrict network access with modern forwarding.
How to check moderator permissions on Minecraft server?
Give the moderator permissions that only allow him to do what he can do. Player management, world editing, and server settings can be separate permission groups.
How to read Minecraft’s latest.log file
The most valuable information when examining a bug is the fault time, the affected component, and the initial fault chain. Just reading the last line is often not enough.
How to implement safe maintenance mode on Minecraft server?
The purpose of maintenance is to limit new player entry, notify existing players, and verify normal access when the update is finished.
How to separate game IP and administrative access on Minecraft server?
Separating the game connection available to players from management ports reduces unnecessary access. You can use a direct server, proxy or provider service as the connection path.
How to check if the Minecraft plugin file is reliable?
Since plugins run within the server process, verify their source, version, and requirements before installing them. File name or popularity alone is not proof of trust.
Appearance and monitoring
How to change Minecraft server MOTD?
MOTD is the short description the player sees in the server list. In Java the text is usually set in the server.properties file, in proxy networking the proxy the player connects to.
How to use Minecraft MOTD color codes?
The color format depends on the software that reads the MOTD. Vanilla properties, plugin using legacy format, and MiniMessage may not expect the same input syntax.
How to make color transition with Minecraft MiniMessage?
In plugins that support MiniMessage, the color transition is written with a label. Check MiniMessage support separately for the relevant area of the settings file.
How to prepare Minecraft server-icon.png?
The icon for the Java server list must be a 64×64 pixel PNG named server-icon.png in the server's working directory.
How to make a live banner for Minecraft server?
The live banner broadcasts the Minecraft status as a visual. You can start with a ready-made template or edit your own design.
How to add Minecraft server widget to website?
The iframe widget allows you to embed server status on your site. First, choose the theme and size according to the area where you will place it.
How to find out the version of the Minecraft server?
The version field in the status query gives an initial information. On proxy networks, this label may not indicate all supported client versions.
How to read Minecraft server player count history?
Current player count is one metric. To understand peak hours, look at a history chart with time range, sampling, and last metered time.
How to calculate Minecraft server uptime?
Uptime depends on how availability is measured during the particular period. For evenly spaced checks, the rate of successful checks provides an approximation.
How do two Minecraft servers compare?
Number of players and delay alone are not enough for server selection. Comparison with connection information on the same edition and similar measuring hours.