Killing Floor 2 Guide: Online Matchmaker and How to Make and Join a Server

Everything you need to know about how to choose, join, and make your own KF2 server.

Everything you need to know about how to choose, join, and make your own KF2 server.

The server browser has gotten a bit of an update since KF1 – and not just in looks. There’s a lot more you can do with it now to ensure that you are able to get into a game with your friends. 

Here are some things to know.

How Do I Find and Join a Server?

It all depends on what you’re looking for! Right now, the options are rather simple – even more so if you want them to be whitelisted (i.e. for credit towards achievements and gaining perk levels). 

There are hundreds of KF2 servers up now, so you have plenty of choices, and the filters seem to be working now too. 

Here are some things to look for:

  • Difficulty – do you want to play Normal, Hard, Suicidal, or Hell on Earth?
  • Game Type – this is generally defaulted to Survival
  • Number of Players – servers with 7+ players don’t give XP or achievements as of the latest patch
  • Map (these are typically on rotation so it shouldn’t matter too much unless you’re gunning for a particular map achievement and don’t want to wait)

Since KF2 doesn’t play nice if there’s high lag, I recommend sorting the servers by Ping, the very last option with the three bars on the list screen. The lower the better.

Other filters you should consider:

  • No password
  • No full servers
  • No empty servers (if you don’t like playing alone)

Once you have found the server you want, just double-click the server name or press the Join button.

Using the online matchmaker is very similar, although in early release days it has been problematic so most people have just defaulted to Browse Server. With the matchmaker, you have the added ability to search and join games that haven’t started yet, where all players are still in lobby.

How to Join a Server With Friends

There are two ways to join a server with your friends, both of which are fairly easy:

Join on a friend already in a server through Steam

This is the first method and was pretty much the only way you could get into a game with your friends in KF

  • Using the Steam overlay (or just through the Friends window), right click and Join Game or have them send you an invite through Steam. 
  • Note: With this method, you cannot guarantee that other people won’t join the server before you, losing a spot in that server.
Make a lobby/group first before joining a server

The simplest way to ensure that everyone gets into a game at the same time is to make a group first.

  • The group leader (whoever starts adding friends first) should have at least of the other members as friends on Steam.
  • Click the (+) just underneath your username on the right-hand side of the menu where there are five empty player slots.
  • It will open up the Steam overlay. Click the Invite button next to their Steam name.
  • Note: Other players can add people to the lobby once they have joined, it does not have to be the group leader that invites everyone.

How to Start Your Own Dedicated Server

Since it’s not always easy to find an empty server for you and your friends, or if you want to be able to tweak the settings of a server just the way you want it, Tripwire still advises you not to use the dedicated server tool through Steam

Instead, follow these instructions from the KF2 wiki:

Downloading and Running the SteamCMD Update Tool
  1. Download the SteamCMD Update Tool:
  2. Extract the contents to a directory (Windows example: C:SteamCmd).
    Do not extract the contents of the updater tool to the regular Steam Client folder or to a folder that has the older HLDSUpdateTool program.
  3. Launch SteamCmd
NOTE: To automate this process for future updates, see #Automating SteamCmd.
    1. Open a command prompt in that directory and start SteamCmd
      • Windows: Type steamcmd
    The program will automatically update and enter you in to a Steam> prompt. Type help for more information.
  1. Log in with your Steam Account. We recommend server admins set up a server steam account for this process.
You must log out of the regular Steam client in order to properly log in to SteamCMD Update Tool (if you use your personal steam account)
login username password 
4a. If you receive a Steam Guard error, check your e-mail for your access code and execute the following commands (you’ll only need to do this once):
set_steam_guard_code yourcodehere login username password 
4b. You can also log in as: anonymous
 login anonymous 
5. You should see a message stating that you have successfully logged in with your account.
Downloading the Killing Floor 2 Server
This describes the process of updating the KF2 dedicated server application. These steps are required every time the game is updated. To automate this process for future updates, see #Automating SteamCmd.
1. If you aren’t proceeding from the previous set of instructions, first launch SteamCmd.
2. At the Steam > prompt, set your KF2 Dedicated Server install directory.
Absolute Path:
force_install_dir c:KF2Server 
Up one folder:
force_install_dir ..KF2Server 
In the Steam Command folder:
force_install_dir .KF2Server 
3. Install or Update KF2.
If this is your first time installing or if you are trying to verify the integrity of the server files:
app_update 232130 validate 
If this is simply an update to an existing KF2 dedicated server:
app_update 232130 
If Tripwire is currently running a beta update of the dedicated server files:
app_update 232130 -beta "branch name" 

Where “branch name” is the current beta branch. Currently there is not a live dedicated server beta branch.

4. Once finished, type quit at the Steam> prompt to properly log off of the Steam servers.
Automating SteamCmd

There are two ways to automate SteamCmd.

1. Add commands to the command line. Example:
SteamCmd +login user password +force_install_dir ./kf2_ds +app_update 232130 validate 
2. Create a script.
a. Put your SteamCmd commands in a text file. Example:
// update_kf2_ds.txt // login anonymous force_install_dir ./kf2server app_update 232130 validate exit 
b. Run SteamCmd with the +runscript option. Example:
SteamCmd +runscript kf2_ds.txt 
Starting the Server

Use the batch file downloaded with the server or create your own. To launch a server with default settings on Survival Biotics Lab use the following batch script:

start .Binarieswin64kfserver kf-bioticslab 

Currently the server has several dependencies. As such we have shipped the UE3Redist.exe with the server files and it can be found in the “BinariesRedist” sub folder of where you have installed the server from SteamCMD.


By default the server will use the following ports:

Port Default What this option controls
Game Port 7777 This is the main port the game will send connections over
Query Port 27015 This port is used to communicate with the Steam Master Server
Web Admin 8080 This port is used to connect to your servers web admin page (if turned on)
Steam Port 20560

If you have any other issues with regards to joining and playing on a server, please feel free to leave a comment! 

For other helpful articles and guides for playing Killing Floor 2:

About the author

Stephanie Tang

Avid PC gamer, long-time console lover. I enjoy shooting things in the face and am dangerously addicted to pretty. I'm also a cat.