Container unhealthy due to ping failures - Paper 1.19.4 on image 2025.12.1

[mhbates]

Describe the problem

The latest image (2025.12.1) was throwing the following error for me and showing unhealthy status for the container. This is on Paper 1.19.4. Rolling back to image 2025.12.0 fixes it.

failed to ping localhost:25565 : Received invalid packet. Expected #0, got #26

Container definition

docker run -d \
--name minecraft \
--cpus="2.0" \
-p 25565:25565 \
-p 8123:8123 \
-v /home/ubuntu/minecraft:/data \
-e EULA=TRUE \
-e SERVER_NAME=xxx \
-e ENABLE_RCON=true \
-e MOTD="xxx" \
-e DIFFICULTY=hard \
-e ENABLE_WHITELIST=true \
-e ENFORCE_WHITELIST=true \
-e WHITELIST=xxx \
-e OPS=xxx \
-e FORCE_GAMEMODE=true \
-e GENERATE_STRUCTURES=true \
-e ANNOUNCE_PLAYER_ACHIEVEMENTS=true \
-e ONLINE_MODE=true \
-e SEED="-6467775105471627794" \
-e SPAWN_PROTECTION=1 \
-e PVP=true \
-e TZ=America/New_York \
-e MEMORY=5G \
-e TYPE=PAPER \
-e USE_AIKAR_FLAGS=true \
-e VERSION=1.19.4 \
-e ENABLE_AUTOPAUSE=false \
-e UID=1001 \
-e GID=1001 \
--restart=always \
itzg/minecraft-server

Container logs

failed to ping localhost:25565 : Received invalid packet. Expected #0, got #26