Securing your Minecraft server against griefers can involve multiple strategies, ranging from technical solutions to community management practices. Here are a few steps you can take:
Whitelist Your Server: By setting up a whitelist, you ensure that only players you've pre-approved can join your server. This is an effective way to keep out unknown individuals who might cause trouble. To enable whitelisting, you simply set the "white-list" variable to "true" in your server.properties file, and then add approved usernames to the whitelist.json file.
Set Up Permissions: A permissions plugin like LuckPerms for Bukkit, Spigot, or Paper servers lets you specify which actions each player (or rank of players) can take. By limiting certain potentially destructive actions (like using TNT or lava buckets), you can protect your server from griefing.
Use a Grief Prevention Plugin: Plugins such as GriefPrevention or CoreProtect allow players to claim their own land where only they can build or destroy blocks. CoreProtect even provides a way to roll back any griefing that occurs, restoring blocks to their previous states.
Establish Clear Rules: Make sure your players understand what is and isn't acceptable behavior. Clear rules about griefing, shared resources, and player interactions can help prevent misunderstandings that lead to destructive behavior.
Moderation and Active Admins: Having a team of trusted moderators or admins who can enforce rules, ban disruptive players, and generally keep the peace can be an effective deterrent against griefing.
Regular Backups: Regularly backing up your server can save a lot of headache in the event of a major griefing incident. If all else fails, you can restore your server to a pre-griefing state.
Community Building: Lastly, fostering a strong, respectful community can help discourage griefing. If players feel a sense of belonging and ownership over the server, they'll be less likely to harm it and more likely to self-police against griefers.
Remember, no solution is 100% foolproof. The key is to combine these strategies to create a layered defense against griefers.