Check if your Arma 3 server is online
Arma servers use a short run of consecutive UDP ports, and queries are answered on a different one from the game itself.
The ports Arma 3 uses
Players enter the game port; queries are answered on the port directly above. Forward the game port alone and the server can be joined but seen by no list and no checker. Arma puts other services on more ports in the same block, so one range rule is safer than several single entries.
Every port a default Arma 3 install uses
With the game port left at 2302. If you changed it with -port=, the other ports move with it.
| Port | What it is for |
|---|---|
| 2302 UDP | Game trafficRequired The port players type. |
| 2303 UDP | Steam queryRequired Arma places its query port at game port + 1. |
| 2304 UDP | Steam masterRequired Registration with the master server list. |
| 2305 UDP | VONRequired Voice-over-network. Skip it and in-game voice fails while everything else works. |
Still offline? Try this
Forward the range instead of the one port and try again. If the query still fails, make sure the server has finished loading its mission and mods — a heavily modded server can take a long time before it answers, and BattlEye starting up adds more.
What a Arma 3 server needs to run well
- Memory, 40 players
- 8 GB
- CPU cores
- 4+
- Disk
- 40 GB+
AI pathfinding is the bottleneck and is largely single-threaded. Player count barely matters by comparison.