MCUtility

server.properties settings to check before you open a server

Before a Java Edition server goes public, check these settings in server.properties. Each one decides who can join, what is reachable from the internet or what ends up in your logs. Restart the server after changing any of them.

Java Edition · Checked against Java Edition 26.3 · Published

Who can join

SettingSafe valueWhy
online-modetrueChecks every player’s account. With false, anyone can join using any name, including yours, unless a proxy in front of the server checks accounts.
white-listtrue for private serversOn by default since 26.3. Turn it off only if the server should be open to everyone.
enforce-whitelisttrueKicks players who are removed from the whitelist when it’s reloaded.
enforce-secure-profiletrueOnly lets in players with a Mojang-signed chat key, so chat messages can be reported.

What is exposed to the internet

SettingSafe valueWhy
enable-rconfalse unless neededRCON gives full console access and isn’t encrypted. If you use it, set a long rcon.password and don’t forward port 25575 on your router.
enable-queryfalse unless neededAnswers query requests with server details and the player list over UDP.
management-server-enabledfalse unless neededStarts an API that can manage the server. Keep TLS on and the host set to localhost unless you know you need more.
server-ipemptyEmpty listens on every network interface, which is what almost every server wants.

What players can see and what gets logged

  • hide-online-players=true stops the server list and status checks from showing who is online.
  • enable-status=false hides the server from server list pings completely. Players can still join if they know the address.
  • log-ips=false keeps player IP addresses out of the console and log files.

Settings that behave unexpectedly

  • spawn-protection needs an operator. If nobody is an operator, spawn protection is off, whatever the radius.
  • view-distance costs performance. Each step adds a ring of chunks per player. Lower it before buying more hardware.
  • PvP isn’t here any more. Since Java Edition 1.21.9 it is the pvp game rule.

The server.properties Generator shows a short warning next to risky values, and the settings reference lists every option.