Wrong timezone used in some log entries

[roworu]

Describe the problem

Docker logs show incorrect time on most of log entries, despite time being correct inside container itself:

roworu@debian-server:~/docker/minecraft$ docker exec -it minecraft date 
Thu Jul 17 12:26:42 EEST 2025
roworu@debian-server:~/docker/minecraft$ date
Thu Jul 17 12:26:46 EEST 2025

Here is an example from recent container restart, some entries show correct time (12 EETC), some are not (9 UTC):

roworu@debian-server:~/docker/minecraft$ docker logs minecraft
[init] 2025-07-17 12:21:56+03:00 Running as uid=1000 gid=1000 with /data as 'drwxr-xr-x 1 1000 1000 640 Jul 17 11:59 /data'
...
[init] 2025-07-17 12:22:17+03:00 Starting the Minecraft server...
...
[09:22:19] [main/INFO]: Loading Minecraft 1.21.7 with Fabric Loader 0.16.14
[09:22:20] [main/INFO]: Dependencies overridden for noisium
[09:22:20] [main/INFO]: Loading 81 mods:

Should that be reported upstream? Or am I missing some ENV options to pass timezone info to server itself?

Container definition

services:
  minecraft:
    image: itzg/minecraft-server:java21-graalvm
    tty: true
    stdin_open: true
    container_name: minecraft
    ports:
      - "25565:25565"
    environment:
      LOG_TIMESTAMP: "TRUE"
      EULA: "TRUE"
      MOD_PLATFORM: MODRINTH
      MODRINTH_MODPACK: https://modrinth.com/modpack/sop/version/1.21.7-2.1
      MODRINTH_PROJECTS: skinrestorer, vtps, hardcore-revival, balm
      INITIAL_ENABLED_PACKS: minecart_improvements
      SNOOPER_ENABLED: "FALSE"
      VIEW_DISTANCE: 16
      SIMULATION_DISTANCE: 16
      SPAWN_PROTECTION: 0
      DIFFICULTY: "hard"
      SYNC_CHUNK_WRITES: "FALSE"
      ENABLE_AUTOPAUSE: "TRUE"
      HARDCORE: "TRUE"
      ONLINE_MODE: "FALSE"
      AUTOPAUSE_TIMEOUT_INIT: "3000"
      AUTOPAUSE_TIMEOUT_EST: "3000"
      INIT_MEMORY: "512M"
      MAX_MEMORY: "4G"
      ENABLE_RCON: "FALSE"
      MAX_PLAYERS: "5"
      USE_MEOWICE_GRAALVM_FLAGS: "TRUE"
      USE_MEOWICE_FLAGS: "TRUE"
      MAX_TICK_TIME: "-1"
      DATAPACKS: "/datapacks/"
      OPS: roworu
      ENABLE_WHITELIST: "FALSE"
    restart: unless-stopped
    volumes:
      - "/etc/timezone:/etc/timezone:ro"
      - "/etc/localtime:/etc/localtime:ro"
      - ./main/data/:/data:Z
      - ./main/datapacks:/datapacks:Z

Container logs

[itzg]

Try this https://docker-minecraft-server.readthedocs.io/en/latest/configuration/misc-options/#timezone-configuration

[roworu]

Providing needed timezone as ENV like TZ=Europe/London worked fine, thank you!

To be honest, I thought that just mounting /etc/timezone is enough.

[itzg]

I believe different apps and their libraries look to either mechanism, which is why setting both seems to be the definitive solution.