In this guide, I’ll explain how to install and configure a L4D server on CentOS 7.

Installing Left 4 Dead

Before we get started, we have to make sure that the system is up-to-date and secure. We’ll also need to create a new user for the server. When prompted, specify a strong, secure password for this user.

yum update
yum upgrade -y
adduser l4d
passwd l4d

The necessary firewall ports required by Left 4 Dead have to be opened, so let us do that before we move on.

firewall-cmd --zone=public --add-port=27015/tcp --permanent
firewall-cmd --zone=public --add-port=27015/udp --permanent
firewall-cmd --reload

The required system libraries needed to run SteamCMD have to be installed.

yum install glibc.i686 libstdc++.i686 -y

Switch to the user account that we created earlier.

su l4d
cd ~

Download the SteamCMD software.

wget https://steamcdn-a.akamaihd.net/client/installer/steamcmd_linux.tar.gz
tar xf steamcmd_linux.tar.gz

Up next, we have to use SteamCMD to install the game server files.

./steamcmd.sh +login anonymous +force_install_dir ./l4d +app_update 222840 validate +quit

When the screen reads Success! App '222840' fully installed., the server has been installed.

Customizing the server

Server customization is done by editing the server.cfg file.

nano ~/l4d/left4dead/cfg/server.cfg

Populate server.cfg with the following text. Be sure to change ServerName and RconPassword to your desired server name and rcon password (server admin).

hostname "ServerName"
rcon_password RconPassword

Updating your server

Create the file update_l4d.txt in the users home directory.

nano /home/l4d/update_l4d.txt

Populate that file with the following contents.

login anonymous
force_install_dir ./l4d
app_update 222840
quit

Update your server any time by running the following command.

cd ~ && ./steamcmd.sh +runscript update_l4d.txt

Running your server

To start your server, run the following commands.

cd /home/l4d/l4d/
screen -dmS l4d ./srcds_run -console -game left4dead -port 27015 +map l4d_farm04_barn +maxplayers 4 +exec server.cfg 

The server is now running in a background screen session.

To shut down the server, run the following command.

screen -S l4d -X quit

Enjoy your new Left 4 Dead server!