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🌐 Network Service

Updated May 15, 2026

🌐 Network Service

The Network service provides critical connectivity diagnostics, port management, and server discovery tools to ensure that ARK servers are reachable by players and correctly configured for the internet.

📝 Service Overview

  • File Path: src-tauri/src/services/network.rs
  • Protocol Support: TCP (Connectivity), UDP (Source Engine Query), HTTP (IP Discovery).
  • Core Functionality: Public IP Resolution, Port Availability Testing, Server Health Querying (A2S).

🚀 Key Features

1. External Connectivity Testing (📡)

  • Public IP Resolution: Automatically fetches the host's WAN IP address via ipify.org, allowing the manager to provide ready-to-use "Copy IP" buttons for cluster members.
  • Inbound Port Audit: Attempts to establish a remote connection to the server's Query and Game ports to verify that Port Forwarding and Firewall rules are correctly configured.

2. Smart Port Management

  • Conflict Detection: Before starting a server, the manager uses the is_port_in_use heuristic to check if the target ports are already occupied by another ARK instance or system process.
  • Dual-Protocol Validation: Since ARK uses both TCP (RCON) and UDP (Query/Game), the service validates availability for both protocols before confirming a port as "Free."

3. A2S Server Query (🔍)

The service implements the native Source Engine Query (A2S_INFO) protocol to verify the actual state of a running server:

  • UDP Heartbeat: Sends a specialized binary packet (0xFFFFFFFFTSource Engine Query\0) to the server's Query port.
  • Readiness Verification: A server is only marked as "Online" in the UI once it successfully responds to this query, indicating the engine has fully loaded and is listening for players.
  • Timeout Protection: Uses a strict 2-second timeout window to prevent unresponsive servers from causing UI lag.

🛠️ Technical Details

A2S Query Packet

The service manually constructs the binary request to minimize dependencies:

let request = [
    0xFF, 0xFF, 0xFF, 0xFF, // Header
    0x54,                   // 'T' (A2S_INFO)
    0x53, 0x6F, 0x75, 0x72, 0x63, 0x65, 0x20, 0x45, 0x6E, 0x67, 0x69, 0x6E, 0x65, 0x20, 0x51,
    0x75, 0x65, 0x72, 0x79, // "Source Engine Query"
    0x00,                   // Null terminator
];

Local Bind Logic

Verifies port availability by attempting an ephemeral bind:

pub fn is_port_in_use(port: u16) -> bool {
    TcpListener::bind(("0.0.0.0", port)).is_err() || UdpSocket::bind(("0.0.0.0", port)).is_err()
}

🎨 Developer Notes

  • Reliability: IP discovery uses a 5-second timeout and reqwest for robust handling of intermittent network issues.
  • Port Ranges: Administrators should ensure that ports tested by this service are also allowed in the Windows Advanced Firewall and any upstream routers.
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