3 warnings found. Every finding below comes from what was actually in the pasted files. Treat the fixes as suggestions: they cover the common causes, and this case may need more digging.
Paper 1.21.11-132-ver/1.21.11@c5eb079Minecraft 1.21.11
What this error means, and every way to fix it →
This log contains 3 lines logged at ERROR level. Roastd checked them against its failure signatures and none matched, so they are classified as benign. A plain count of ERROR lines will always be higher than the number of findings here.
This server is issuing offline-mode identities (bozli123 got a name-derived UUID)
The UUIDs handed out at login are version 3, generated from the username instead of issued by Mojang (bozli123 was given 45acb7a3-d5b1-3090-939a-723881ed9c5d). That means online-mode=false, or a proxy in front that is not forwarding real identities. Two consequences, both worse than they look. Anyone can join under any name, including your admins, because nothing checks the account. And the UUID is the player identity: flip online-mode back to true and every inventory, home, claim and permission tied to the old UUID looks lost, because the player is now a different person to the server. Set online-mode=true in server.properties before the world has history, or configure proper forwarding if a proxy is meant to be handling authentication.
jump to line 562The whitelist is turning players away: 4 rejected joins here
white-list=true and the account trying to join is not on the list. This is the usual reason an owner cannot join their own freshly installed server. Add the account from the console with "whitelist add <name>", exactly as the account is spelled, then "whitelist reload". To open the server up instead, set white-list=false in server.properties and restart. Bedrock players joining through Geyser need their Floodgate name (with its prefix) on the list, not their Java name.
Why this happens: Whitelisting players →jump to line 564ProtocolLib does not match this Minecraft version
ProtocolLib, or a plugin built on it, predates the Minecraft version you run. Its internals reach into server code that moved. Install the latest ProtocolLib build for your exact Minecraft version (dev builds after an update). If errors continue, the plugin using it needs updating too.
jump to line 82As received, after redaction.
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