How do I install BlueMap (3D map) on my Minecraft server?

BlueMap creates a 3D map of your world that anyone can view in the browser, including player positions. It's the modern successor to Dynmap and works as a plugin on Paper and Purpur and as a mod on Fabric and Forge. For an SMP it's handy for spectators, map readers and anyone trying to find someone else's base.

Step 1: install

1. Install BlueMap via your panel's plugin library or upload the jar file to plugins. See installing a plugin.
2. Restart the server. BlueMap creates the plugins/BlueMap folder with configuration files and stops with a message that you need to accept the download.

Step 2: accept the download

BlueMap needs the original Minecraft files to draw blocks. Open plugins/BlueMap/core.conf and set:

accept-download: true

Restart the server. On first start BlueMap downloads the required files and begins rendering in the background. On an existing world that can take several hours and costs CPU; do it at a quiet moment.

Step 3: open the port

BlueMap runs its own web server on port 8100. Assign an extra port to your server in your panel and put it in plugins/BlueMap/webserver.conf:

ip: "0.0.0.0"
port: 8100

Use the port number the panel gave you if it isn't 8100. After a restart the map is available at http://your-server-ip:8100. Only share that link within your group if you don't want the map to be public.

Managing rendering

• /bluemap shows the rendering progress.
• /bluemap stop pauses rendering, for example during a busy evening; /bluemap start resumes it.
• /bluemap render world re-renders a world after major changes.

After the first render, new chunks are updated automatically while players play.

Reducing the load

If you want to save CPU and storage, disable the Nether and End in plugins/BlueMap/maps/ by setting enabled: false in those files, or limit the map to your world border. A world of 3000 by 3000 blocks renders in a few hours and takes up about a gigabyte of storage; bigger worlds scale roughly linearly with that. BlueMap runs fine on a 5 GB RAM server, as long as you don't start the first render during a busy evening.

Alternative: Dynmap

If you'd rather have a lighter 2D map, Dynmap is a fine alternative. The guide is in setting up Dynmap. Don't run both at the same time; that doubles the rendering work with no added value.