First, install the required packages.
sudo apt-get update
sudo apt-get install lib32gcc1 screen wget
Create a directory for your server.
mkdir ~/killingfloor ; cd ~/killingfloor
Download and extract SteamCMD.
wget http://media.steampowered.com/installer/steamcmd_linux.tar.gz
tar -xvzf steamcmd_linux.tar.gz
Run SteamCMD and enter your Steam login identity.
./steamcmd.sh
login <username> <password>
Set the installation directory and wait for the game files to download.
force_install_dir /home/<user>/killingfloor/game/
app_update 215360 validate
Create a startup script for your server.
vi killingfloor.sh
## Paste in these two lines, and save.
cd /home/<user>/killingfloor/game/System/
./ucc-bin server KF-farm.rom?Difficulty=7.0?game=KFmod.KFGameType?VACSecured=true?MaxPlayers=6 -ini=Killingfloor.ini -nohomedir
chmod +x killingfloor.sh
Edit Killingfloor.ini with the settings that you would like to use.
cat /home/<user>/killingfloor/game/System/Default.ini > /home/<user>/killingfloor/game/System/Killingfloor.ini
vi /home/<user>/killingfloor/game/System/Killingfloor.ini
Start your server in screen.
screen -S killingfloor ./killingfloor.sh
Your server is now running, Enjoy!
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