Left 4 Dead 2 Dedicated Server: srcds, server.cfg & Mutation Guide

Data Verified: May 2026

Complete Left 4 Dead 2 dedicated server guide. Configure server.cfg, mapcycle, sv_search_key for matchmaking, mutations, Sourcemod plugins, and size hardware for stable 8-32 slot servers.

Default file locations

Default installation paths for Left 4 Dead 2 dedicated servers installed via SteamCMD.

Windows

C:\srcds\left4dead2\cfg\

Linux

/home/steam/l4d2/left4dead2/cfg/

Pro-Tip: Always stop the server completely before editing configuration files, or the server will overwrite your changes upon restart.

Default ports for port forwarding

Open these on your router and firewall before exposing the server to the internet.

Default ports for Left 4 Dead 2
ServiceProtocolPort
Game PortUDP27015
Query PortUDP27015
RCON / TelnetTCP27015

Frequently asked questions

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Host your own Left 4 Dead 2 server

All hosting guides →

Step-by-step install and deploy walkthroughs (panels, ports, RAM sizing). Pair these with the command reference above.