How to Add a Service Rule for Your Game Server

A service rule tells Sterile which port on your protected IP carries your game, so the filters made for that game are applied to its traffic.

Every game server you protect needs at least one service rule. The rule picks a profile (the filters and rate limits for one game or protocol), the port it applies to, and how hard to filter.

Add the rule

Open Services, choose your service, go to Service rules and choose New rule. The panel asks for four things:

• IP address: the protected IP your players connect to.
• Profile: search for your game by name, for example Minecraft, Rust or CS2. The line under the field says what the profile covers.
• Port: the port your game server listens on.
• Filter level: leave it on the default, Automatic, never below Balanced, unless you have a reason to change it.

Choose Create service rule. The dashboard shows the change rolling out to the nodes that carry your traffic, and the rule is listed under Service rules.

Default ports for popular games

Use the port your server is really configured with. If you have not changed it, these are the defaults:

• Minecraft Java: TCP 25565
• Minecraft Bedrock: UDP 19132
• Rust: UDP 28015
• Counter-Strike 2 and Garry's Mod: UDP 27015
• ARK: UDP 7777
• FiveM: 30120, on both TCP and UDP
• TeamSpeak voice: UDP 9987

A game that listens on both TCP and UDP needs one rule for each protocol, with the matching profile.

Choosing a filter level

Each level filters as if an attack of a certain size were already under way:

• Standard: the lightest filtering, with protocol checks and generous limits.
• Balanced: recommended, and the default. Filters as if a low attack is always under way.
• Strict: filters as if a medium attack is always under way. For services that are attacked often.
• Maximum: the strictest checks and limits. Meant for a sustained attack, and it can affect legitimate players.

With Automatic on, the level you pick is a floor: filtering is raised during an attack and steps back down once it is over, but never below that level. Turn Automatic off to pin the rule to exactly the level you chose.

Drop unsolicited UDP

UDP profiles have one more switch, Drop unsolicited UDP. It is only for services your server connects out from, where nothing should ever arrive that the server did not ask for. Leave it off for game servers: anything players connect into stops working on that rule when it is on.

Reading and changing your rules

Each rule shows the attack level the network is seeing on it right now: Normal, Elevated, Under attack or Heavy attack.

Open a rule to change its profile, port or filter level. Changing only the filter level keeps the rule as it is. Any other change goes back to the profile's rate limits, so if you gave the rule its own limits, set them again afterwards. To change many rules at once, use Select rules to delete them, set their filter level or move them to another profile together.

Next steps

• Tune how much traffic each player may send in Rate limits in a profile.
• Running a Steam game? Read about the A2S challenge.
• Not set up yet? Start with How to Set Up Your GRE Tunnel With the Installer.

If a rule does not behave as you expect, create a ticket with the port and the game, and we will take a look.