RealFin
Game servers

Hosting a Valheim dedicated server with Docker (the setup I use)

by RealFin · 15 Oct 2026 · 2 min read

My friends and I play Valheim on a dedicated server running on my homelab, so the world is always there, even when the person who “hosted” isn’t online. Here’s the exact setup, using the excellent lloesche/valheim-server image.

What you need

  • A Linux box with Docker. Valheim is light: my server uses ~1.4 GB of RAM and ~16 % of one CPU core with four players.
  • UDP ports 2456–2457.
  • Upload bandwidth: roughly 0.5–1 Mbit/s per player.

docker-compose.yml

services:
  valheim:
    image: lloesche/valheim-server
    container_name: valheim
    cap_add:
      - sys_nice
    ports:
      - "2456-2457:2456-2457/udp"
    volumes:
      - ./config:/config        # worlds, backups, admin/ban/permit lists
      - ./data:/opt/valheim     # server files (re-downloadable)
    environment:
      - TZ=Europe/Berlin   # your own time zone
      - SERVER_NAME=My Valheim Server
      - WORLD_NAME=Dedicated
      - SERVER_PASS=${SERVER_PASS}
      - SERVER_PUBLIC=false
      # only update when nobody is online
      - UPDATE_IF_IDLE=true
      # built-in world backups: hourly, keep 3 days
      - BACKUPS=true
      - BACKUPS_CRON=0 * * * *
      - BACKUPS_MAX_AGE=3
    stop_grace_period: 2m
    restart: unless-stopped

Put the password in a .env file next to it (SERVER_PASS=..., at least 5 characters, and it must not contain the server name). Then:

docker compose up -d
docker logs -f valheim

The first start downloads the server (~1 GB) from Steam. When the log says Game server connected, it’s ready.

Settings worth explaining

  • SERVER_PUBLIC=false: the server doesn’t appear in the in-game community list. Friends join by address. Less random traffic.
  • UPDATE_IF_IDLE=true: Valheim updates often, and a client/server version mismatch means nobody can join. This updates automatically, but never kicks people mid-session.
  • stop_grace_period: 2m: on docker compose stop the server saves the world before exiting. Docker’s default 10 seconds can cut that short.
  • Backups: zip files land in ./config/backups. The world itself lives in ./config/worlds_local.

How friends connect

In Valheim: Start Game → Join Game → Add server, then enter your-address:2456 and the password.

  • Same house: use the server’s LAN IP.
  • From outside: either forward UDP 2456–2457 on the router, or have everyone join over a VPN like Tailscale. A port forward is the only open port I’d consider for a game, because joining is password- or whitelist-protected. Still, think about it first.

World settings (modifiers)

The in-game “World Modifiers” (combat, death penalty, resources, raids, portals) can be set from the server too:

- SERVER_ARGS=-modifier deathpenalty veryeasy -modifier resources most -modifier raids none

The server log confirms them on start: Setting world modifier: raids->none.

Next steps

More in Game servers