Network ports

For the web panel to manage a game server it has to reach two things on that server: the query port (UDP, to read the map and player list) and the RCON port (TCP, to push admin commands). On a stock Source server those are the same number — usually 27015.

What needs to be open

From the web panel’s perspective:

• Outgoing UDP to each game server’s port — the panel sends an A2S_INFO query and waits for the reply.
• Outgoing TCP to each game server’s port — the panel opens an RCON session to push commands.

From the game server’s perspective:

• Incoming UDP on its port — for the panel’s query and for players joining.
• Incoming TCP on its port — for the panel’s RCON connection.

On a typical setup these are all the same port (27015 by default), just two different protocols. If your firewall lets you specify one or the other, you usually need both.

Behind NAT / a home router

If you’re hosting at home or anywhere with a NAT-ing router, you’ll need port-forwards on both UDP and TCP for the game server’s port to its LAN IP. Most consumer routers expose this under “Port forwarding” or “Virtual servers”.

The web panel doesn’t need any inbound ports of its own beyond HTTP (80) or HTTPS (443).

Troubleshooting

If your panel shows the server as offline or with no player list, the most common cause is a firewall blocking one of these ports.

The walkthrough is in Server connection issues — it includes a small sb_debug_connection.php tool you can run from the panel host to test the UDP and RCON sides independently.