Multiplayer

Factorio supports multiplayer games in additional to the single-player campaign and scenarios. By default, multiplayer games run the CO-OP freeplay scenario where all players work together to launch a rocket with a satellite into space. Other scenarios, including PVP maps, are available for download from the forums.

Currently, joining a multiplayer game requires either that all players be on the same LAN or that the host have a public IP address. The next version of Factorio, 0.13, will support a public multiplayer game lobby for locating games as well as NAT punching to make connecting to a server without a public IP address more seamless.

History

Multiplayer games were introduced to Factorio with version 0.11.0. The only connection method available was peer-to-peer mode which meant a low latency connection was required between all players. Gameplay was optimal on LANs, especially with more then two players, as otherwise there could be a noticeable lag between player actions and those actions happening. As of version 0.12.0 the game features "latency hiding" mechanics which make the lag less noticeable or hide it entirely. There is also support for a running dedicated server in headless mode (no graphics) in versions 0.12.0 and beyond. In 0.12.4, peer-to-peer connections are optional as all the server can relay messages from one client to the other clients.

Because of the potentially immense amount of activity on a map, the game engine utilizes a lock step architecture. All instances of the game run full simulations of the entire world and only player actions are transferred across the network.

Playing over LAN / Internet

Playing over Internet was not thought to work properly with version 0.11. Noticeable lag could occur depending on connection speed/reaction time. This has become less of an issue with the latency hiding mechanics introduced in version 0.12, but can still cause issues if there is a significant latency between players.

• Both game instances need the installation of exactly same game-versions and mods. (Tip: Maybe someone has the scenario pack mod off?)
• For a more fluid game the "clients" can turn off autosave.
• Factorio uses the port 34197. The port can be changed in the config.
• Factorio uses UDP only, so make sure, you configured your router correctly. (The game builds it's own "reliable delivery" layer built on UDP to deal with packet loss and reordering issues.)
  • Make sure, that there is no firewall or anti-virus blocking the UDP-packets.
  • read further, look into "more guides", to configure your router set up.
  • It is necessary that all of the peers can communicate with each other. It is however in theory not necessary that all the peers have public IP address - this should work even behind a NAT. See Cube in Cannot Have 3+ Players connected at the same time.
• The hard limit for the number of players is 65535. :)

Voice Chat

• it is recommended to use voice chat (TeamSpeak, Skype), because you need to talk a lot (coordinate connection, building, handling attacks...). TeamSpeak servers are posted in the multiplayer forum.

Finding other Peers

• use the multiplayer board in the forum.
• many players use other software like Hamachi or Evolve to meet other players. This has the "advantage" of creating a virtual private network between the players. See down under software.
• some use also Steam to find others.

Factorio servers or Why Peer-to-Peer?

There were some discussions about, why Factorio doesn't use the client+server-model, but instead uses the peer-to-peer priniciple.

As of version 0.12.X there is support for a Dedicated Server option, but this still functions with the same peer-to-peer networking.

Some links

• developer statement
• Older statement
• Good explanation

Dedicated/Headless server

This article contains content on features that are included in 0.12.X, an "experimental release" of the game that is not considered as "stable release" by the developers yet.

As of Factorio version 0.12.0 onwards, a dedicated (or headless) server can be started using the '--start-server' command line option.

In this mode:

• Graphics are not initialized (faster start up, less memory usage, works on completely headless servers)
• Game starts immediately and loads a save given as a parameter to the command
• The server has no character in game
• Game is paused while there are no players connected
• Saves the game on exit (and autosaves normally)

You will need to create your save file before you start the server, as the dedicated server REQUIRES a save file to be provided. This can easily be done by loading up a game in Single-Player and saving it right away.

Below are basic instructions for starting a dedicated server on Windows and Linux.

Windows

• Go to your Factorio.exe folder (Probably 'C:\Program Files\Factorio\bin\x64\')
• Create a text document and write into it 'Factorio.exe --start-server YOURSAVEGAME.zip'
  • If you haven't already done, replace YOURSAVEGAME with your savegame name
• Save the file as server.bat. Important: At 'Save as type:' select 'All Files'
• Use the server.bat to start your server.
• The console log will be shown in the window.
• To close the server, select the console window press Control+C. If you just close it without pressing this, it will not save your game.
• Forward Ports: You will find detailed instructions for your specific router on the web

Linux

This step-by-step guide has been verified on fresh CentOS 7 and RHEL 7 installs but should be applicable with little to no changes on most distribution.

The guide assumes you will install the headless server under /opt/factorio, adjust paths according to your own setup. We will also suggest that you run the Factorio server as a separate user to harden security of your setup.

This guide does not handle firewall/port forwarding since this can be done in various ways on Linux (make sure to read up how this is done as a Linux admin on your particular distribution)

You can use the Linux factorio-init script to start/stop your headless server in a much better way. The script will ensure you only ever use the most recent save when your server starts (even if that was an auto-save) while also letting you set a number of other settings like Autosave frequency and Latency settings. This script will also simplify updating the server when combined with the Linux factorio-updater script.

• Download the at least v 0.12.0 Experimental Version and upload the linux tar.gz package to your server /tmp
• Extract the package to /opt/factorio

#cd /opt/
#tar -xzf /tmp/factorio.tar.gz

• Check the binary to find if you need any libs installed

#ldd /opt/factorio/bin/x64/factorio
        libasound.so.2 => not found
        libX11.so.6 => not found
        truncated ....

• Install each of the missing libs, i.e the ones labelled "not found" using your distro's package handler
  • It will ask to install graphics and audio libraries as well, but will not use them in headless mode.

# yum whatprovides libasound.so.2
alsa-lib-1.0.28-2.el7.i686 : The Advanced Linux Sound Architecture (ALSA) library
Repo        : base
Matched from:
Provides    : libasound.so.2

# yum install alsa-lib libX11 <and all other "not found" libs in your case

• Add a new user to your system and assign ownership of the Factorio dir to it (please, do not run as the root user)

#useradd factorio
#chown -R factorio:factorio /opt/factorio

• Try the binary

#su factorio
#/opt/factorio/bin/x64/factorio --start-server savename

As long as it fails saying it cannot find/open the savename.zip you are set! Just upload a save from your own computer and put it in the /opt/factorio/saves directory

Dedicated/Headless server in version 0.11.X

It was still possible to achieve a Dedicated server in version 0.11.X, but it required some workarounds.

Workarounds in version 0.11.x:

• Linux Headless server / VNC: https://forums.factorio.com/viewtopic.php?f=53&t=6449
• Dedicated Multiplayer Server Guide

Game types

Coop

Coop-game runs without any further preparation ( https://forums.factorio.com/viewtopic.php?f=53&t=6501 )

PvP

• PvP with craftable biters

Forces

You can now set up forces. See this https://forums.factorio.com/viewtopic.php?f=3&t=13512&start=80#p92087

game.create_force('force 1')

Creates a force with name "force 1", default forces are "player", "enemy", "neutral"

"player" is the default force for players

"enemy" is force of biters

"neutral" is special, its not attacked, can use all other forces, can be used by all other forces

game.get_player('friend 1').force = game.forces['force 1']

Changes the force of "friend 1" to "force 1"

game.forces['force 1'].set_cease_fire('force 2', true)

makes "force 1" to cease fire against "force 2", reverse has to be done separately

for v in pairs(game.forces) do game.local_player.print(v) end

list all existing forces

Technical Implementation

• Friday facts article

More Tools/Infos

• use mods for planning. See basic planner, Planning-Tool-Mod...
• look into multiplayer forum, most other questions are answered there.
• Cookbook for setting up a headless server

And always remember that Factorio in v0.11 isn't intended to work well on internet connections, so keep patient. ;)

More Guides

• How to set up Factorio server with cookbook
• How To set up a Factorio Multiplayer Server | Guide | Tutorial, by Teaspoon
• Tips to connect in multiplayer, by Nondre

Miscellaneous tips

• the key for Console commands will now initiate a chat in MP. To execute commands you need to type '/c' before the command!
• Set the player's color using the command

/c game.players[x].color = {r=0.7, g=0.5, b=0.1, a=0.9}

Where x is the player number. r, g and b are for red, green and blue respectively (possible values are between 0 and 1, use the right-most column on http://prideout.net/archive/colors.php). a is alpha channel aka Transparency of the color to the base texture. For single player, leave off the "[x]" to set the color.

Software for routing / establishing connection

• https://forums.factorio.com/viewtopic.php?f=53&t=6393
• https://forums.factorio.com/viewtopic.php?f=53&t=6386
• https://forums.factorio.com/viewtopic.php?f=53&t=7690
• A guide for connecting with Evolve