Server setup

What the server needs

The SRS server is a standalone Windows application. It does not need to be installed inside an IL-2 game directory, and a client installation is not required on a dedicated host.

For each public instance you need:

• the current server files from the release ZIP;
• one unused port, reachable over both TCP and UDP;
• permission to write server.cfg, serverlog.txt, and banned.txt in the instance folder;
• an optional Pilot Roster JSON producer if you want assigned callsigns and aircraft data.

One port, two protocols

SRS uses the same port number for its TCP control connection and UDP voice traffic. Allow and forward both TCP and UDP. The default is 6002.

Install one instance

1. Download the current package from GitHub Releases.
2. Extract it to a dedicated folder such as C:\IL2-SRS\main.
3. Allow IL2-SR-Server.exe through the host firewall for both TCP and UDP.
4. Run IL2-SR-Server.exe. The service starts automatically and creates any missing settings in server.cfg.
5. Confirm that Server Health reaches RUNNING and that Voice Links increases when a client connects.

RUNNING means both the TCP control listener and UDP voice listener are active. DEGRADED means at least one listener is unavailable after the startup grace period; check serverlog.txt and verify that the configured port is not already in use.

Run multiple instances

Use a separate folder and unique port for every instance. This keeps logs, bans, exports, roster files, and supporting files from colliding.

You can also pass a specific configuration file with -cfg=:

IL2-SR-Server.exe -cfg="C:\IL2-SRS\instances\main\server.cfg"

Use the exact lowercase argument shown above. Relative file paths inside server.cfg, including the Pilot Roster path, are resolved from the folder containing IL2-SR-Server.exe, not from the folder containing a custom configuration file.

Example instance layout:

C:\IL2-SRS\
  main\
    IL2-SR-Server.exe
    server.cfg
    banned.txt
    serverlog.txt
  training\
    IL2-SR-Server.exe
    server.cfg
    banned.txt
    serverlog.txt

Configure the instance

Use the server window for normal changes. UI changes are saved immediately, and most radio settings are sent to connected clients without a restart. For every key, default, and restart requirement, see the configuration reference.

The server window also provides:

• a persistent White or Dark theme;
• listener state, uptime, voice-link count, recent transmitters, and memory use;
• direct access to Client Admin;
• channel names, limits, and radio behavior controls.

Update safely

1. Stop the SRS server and confirm the process has exited.
2. Back up server.cfg and banned.txt for each instance. Also preserve any local Pilot Roster source or custom integration files.
3. Extract the new release to a temporary folder.
4. Replace the application files while retaining each instance’s configuration and ban list.
5. Start one instance and confirm RUNNING, a successful client connection, and a ready UDP voice link before updating the remaining instances.

Do not distribute a production server.cfg in a release or support bundle without reviewing it first. It can contain private filesystem paths and reserved integration values.

Files to know

File	Purpose
server.cfg	Persistent server and radio settings
serverlog.txt	Startup, synchronization, roster, network, and voice-routing diagnostics
banned.txt	IP addresses blocked by Client Admin
clients-list.json	Optional generated client export; created only when enabled

The default files are written beside the server executable. Include serverlog.txt when reporting server startup, synchronization, or routing problems.

Quick fault checks

Symptom	Check
Server immediately exits	Another process may already be using the configured port
Clients cannot connect	Allow inbound TCP and UDP on the server port and verify NAT forwarding
Client shows connected but voice is unavailable	Confirm UDP is allowed; Client Admin will show WAITING until the voice endpoint is established
Settings appear to revert	Stop the server before manually editing server.cfg, then restart it
Custom configuration is ignored	Use the exact -cfg="..." argument and verify the service account can read and write the file
Pilot Roster is unavailable	Check the configured JSON path and roster warnings in serverlog.txt

Next guides

• Configuration reference for every supported server.cfg key.
• Radio behavior for security, channels, collisions, and priority transmitters.
• Client administration for health monitoring, mute, kick, ban, and exports.
• Pilot Roster integration for assigned callsigns and aircraft.