Understanding server.properties: every setting explained

server.properties is the first file you open and the last one you really understand. It sits at the server's root, is created on first start, and is read at startup only: edit it with the server stopped, otherwise it'll be rewritten over your changes.

The server.properties generator writes the full file from a few questions, and flags dangerous combinations. Here's what the settings that matter do.

Connection and access

Setting	Default	For a public server
server-port	25565	25565, unless the host imposes another
server-ip	empty	empty: the server listens on every address
online-mode	true	true: only authenticated Minecraft accounts get in
max-players	20	what the machine can really hold
white-list	false	true for a private server or a beta
enforce-whitelist	false	true with the whitelist: also removes players already online

online-mode=false has only two legitimate uses: servers behind a Velocity proxy, which checks accounts for them, and servers open to unauthenticated accounts: which then need an authentication plugin, as explained in Protect your server.

Performance

Setting	Default	Suggested
view-distance	10	8
simulation-distance	10	5 or 6
network-compression-threshold	256	256; -1 behind a proxy on the same machine
entity-broadcast-range-percentage	100	100, or less on a server heavy with entities

View distance says how far the player sees terrain; simulation distance how far the server keeps the world alive, mobs, crops, redstone. It's the second one that's expensive. The details, and everything else, are in Run a server at 20 TPS.

The world and the game

Setting	Default	Good to know
level-name	world	the name of the world folder
level-seed	empty	empty: random seed
gamemode	survival	mode for new players
difficulty	easy	normal or hard for real survival
hardcore	false	true: one death, and the player becomes a spectator
pvp	true	false for a cooperative server; protection plugins refine it area by area
spawn-protection	16	radius around spawn where only operators can build
allow-nether	true	false to close the Nether
max-world-size	29999984	a border is better set with /worldborder

A classic trap: spawn-protection doesn't work as long as no operator exists. And it only protects the spawn: for the rest, you need WorldGuard or GriefPrevention.

What shows in the server list

Setting	Role
motd	the two lines under the server's name
hide-online-players	hides the list of online usernames
enable-status	false: the server no longer answers status requests, and appears offline

The MOTD accepts colours: the MOTD generator writes them and shows the result. Leave enable-status=true: without it, the server looks off everywhere, on CubeVote as in the game.

Remote console and queries

Setting	Default	Advice
enable-rcon	false	true only with a long password, and port 25575 closed in the firewall
rcon.password	empty	never the same as another service's
enable-query	false	true if a website or bot reads the player list through the Query protocol

Useful odds and ends

• enforce-secure-profile: requires players to have a chat signing key. Leave it true, except with Bedrock players via Geyser or without authentication, who don't have one.
• resource-pack, resource-pack-sha1, require-resource-pack: offer (or require) a texture pack for the player on login. Fill in the SHA-1 hash: without it, the pack is downloaded again on every login.
• enable-command-block: false by default. Set it to true if your maps or minigames use them.
• allow-flight: false kicks players suspected of flying. Set it to true if a plugin grants flight (VIP ranks, creative), otherwise they'll be kicked wrongly.

After each change

Restart the server, then check it from outside with the server tester: it shows the MOTD, the version and the number of players as a player sees them, and as they'll appear on your listing.