How to whitelist CS 1.6 in ConfigServer Firewall

I have pretty much whitelisted all known steam ports but people still can't join my server when ConfigServer Firewall is active. Anybody knows how?

Solution 1:

Not sure about GoldSrc games, but by default Source Games use the following ports:

• 27015 TCP - Used for RCON. Overridden using -port or +port.
• 27015 UDP - Used for getting information about the game server. Overridden using -port or +port.
• 27005 UDP - Clients communicate with the server on this port. Overridden using -clientport or +clientport.
• 27020 UDP - HLTV / SourceTV / DOTA TV listen for connections on this port. Overridden using +tv_port or disabled entirely using -nohltv.
• 26900/26901 UDP - Communication with the Steam backend. This replaces the old master server query port. Supposed to be 26900, but some Source games (read: most Source games) have an off by one error and actually use one port higher. Overridden using +steamport