Arma Reforger Startup Parameters: -maxFPS, -config and More
Arma Reforger startup parameters are options added to the server's launch command. The ones most servers need are -config (which points to the server config JSON), -maxFPS (which caps the server frame rate) and -logStats (which logs performance numbers). Most of the rest are for tuning, logging and debugging, and many servers never need them.
This guide explains the parameters listed on Bohemia's Startup Parameters page, which ones override a config file setting and which are worth your time. On ChicagoServers the panel builds the launch line for you. A parameter that has no Startup field can only be added by our staff, so contact support. Checked on 2026-11-15 against the Bohemia Interactive Community Wiki, which lags the game, so confirm after major updates.
-config FILE.jsonloads the server config. It is ignored if you launch with-server. On ChicagoServers the panel passes it for you.-maxFPS: Bohemia heavily recommends a value from 60 to 120 on a dedicated server, because without a limit it can try to use all available resources.-logStatswrites FPS, frame time, memory and counts of players, AI, vehicles and projectiles to the log. The interval is in milliseconds.-bindIP,-bindPortand-AILimitoverride matching config settings. On ChicagoServers the panel assigns your ports.- Change one tuning parameter at a time and measure with
-logStats. The defaults are fine for most servers.
On this page
Where startup parameters go
If you run a server on your own machine, parameters follow the program name on the command line. Each starts with a hyphen and some take a value. For example:
ArmaReforgerServer.exe -config ".\Configs\my_server.json" -maxFPS 60 -logStats 30000On ChicagoServers you do not edit a launch line. The panel starts the server with the settings from the Startup tab, and the launch command, the start script and Extra launch options are staff-only. To use a parameter that has no Startup field, contact support and tell us the parameter and the value you want.
The parameters most servers use
| Parameter | What it does | Notes |
|---|---|---|
-config FILE | Points the server at its JSON configuration. | Ignored when you launch with -server. Passed by the panel on ChicagoServers. |
-maxFPS N | Caps the server frame rate. | Bohemia heavily recommends 60 to 120. |
-logStats [MS] | Logs performance statistics at an interval in milliseconds: FPS, frame time, memory, players, AI, vehicles, projectiles and streams. | Use it during a busy session to see where the FPS falls. The interval is optional. |
-profile PATH | Sets the profile directory. | Logs and downloaded mods go to the profile folder by default. |
-logsDir PATH | Sets where logs and other instance data are stored. | |
-addonDownloadDir PATH | Sets where downloaded mods are stored, in an addons subfolder. | |
-addons ID,ID and -addonsDir PATH | Load mods by ID at start, and add extra folders to search for mods. | For a normal server list mods in game.mods instead. See the mods guide. |
Hosting and network address parameters
| Parameter | What it does |
|---|---|
-bindIP IP | Overrides the bind address in the server config. |
-bindPort PORT | Overrides the game port in the server config. |
-a2sIpAddress IP | Sets the IP the Steam Query (A2S) socket binds to. |
-a2sPort PORT | Sets the Steam Query port. |
-listScenarios | Writes the scenario .conf paths to the log, which is how you find valid scenario IDs for your build. |
-autoreload SECONDS | Reloads the scenario automatically after the number of seconds you give, without shutting the server down. |
-server "WORLD" | Starts a local server with a given world. When you use it, -config is ignored. |
AI and performance parameters
| Parameter | What it does |
|---|---|
-AILimit N | Sets the maximum number of AI. Once the cap is reached no system can spawn more. It overrides aiLimit in the config. |
-aiPartialSim N | The number of batches before all AI have been processed. |
-disableAI | Turns AIWorld off, so AI is not initialised or ticked. |
-disableNavmeshStreaming | Turns navmesh streaming off. |
-jobsysShortWorkerCount N and -jobsysLongWorkerCount N | Number of threads for short and long jobs. They are capped at the CPU count or engine limits. |
The AI-related parameters have matching settings in the operating block of the config, which is the easier place to set them. See the scenarios and performance guide for how they affect the server.
Network tuning parameters
These tune how the server decides what to stream to each player. They are advanced options, so leave them alone unless you have a measured network problem.
| Parameter | What it does | Range or default |
|---|---|---|
-nds DIAMETER | Network Dynamic Simulation: streams only entities that are relevant to a player. Higher values widen the view range and reduce performance. | Default 2 in each direction. 0 turns it off. |
-nwkResolution M | Sets the Spatial Map cell resolution. | 100 to 1000 m |
-staggeringBudget N | Limits how many stationary spatial map cells are processed per tick. | 1 to 10201. If unset it follows the -nds diameter. |
-streamingBudget N | A global streaming budget shared across connections. | Cannot go below 100 |
-streamsDelta N | Limits new streams opened per client when server and client stream counts diverge. | 1 to 1000, default 100 |
-rpl-timeout-ms MS | Sets the client and server timeout. | Value in milliseconds |
Logging and crash parameters
| Parameter | What it does | Default |
|---|---|---|
-logLevel LEVEL | How much is logged: normal, warning, error or fatal. Each level includes the ones below it. | not stated |
-logAppend | Keeps the log history instead of clearing the logs at start. | off |
-keepNumOfLogs N | The maximum number of logs kept. | 10 |
-noThrow | Turns off the error dialogs for script errors, asserts and crashes. | off |
-VMErrorMode MODE | How script VM errors are reported: silent, log_only, full or fatal. | not stated |
-disableCrashReporter | Stops crash-report prompts and automatic sending. | off |
-keepCrashFiles | Keeps the crash files after they have been sent. | off |
disableCrashReporter also exists as a setting in the operating block of the config, with the same effect as the parameter.
Sessions and saves
-autoreload SECONDSreloads the scenario after the delay you give, without shutting the server down.-loadSessionSave [NAME]loads the latest save when no name is given, or the named save. Test it on your own server and build before you depend on it.
Parameters that appear in other guides
Some guides, especially Docker and Linux examples, use options that are not on Bohemia's startup parameters page:
-backendlogis not listed on that page, so treat it as unconfirmed.-publicAddressis a server config key,publicAddress, and not a parameter on that page.- The page lists
-noThrowwith that capitalisation, and the config key isaiLimitwhile the parameter is shown as-AILimit. Copy the spelling from the wiki.
What overrides what
| Setting | Config key | Parameter |
|---|---|---|
| Config file | n/a | -config (ignored with -server) |
| Bind address and port | bindAddress, bindPort | -bindIP, -bindPort override them |
| AI cap | operating.aiLimit (default -1, no limit) | -AILimit overrides it |
| Crash reporter | operating.disableCrashReporter | -disableCrashReporter has the same effect |
| Frame rate cap | none | -maxFPS only |
On ChicagoServers, values with a Startup field, such as the name, passwords, ports and slots, are written from that tab at every start. For anything else, ask support. See the server config guide for every config key, and Arma Reforger server hosting for what is included.
Frequently asked questions
What startup parameters does an Arma Reforger server need?
At minimum -config, which points to the server config JSON. Bohemia also heavily recommends -maxFPS with a value from 60 to 120, and -logStats is useful for measuring performance. On ChicagoServers the panel builds the launch line for you.
What does -maxFPS do on an Arma Reforger server?
It caps the server's frame rate. Bohemia recommends 60 to 120, because without it the server can try to use all available resources.
What does -logStats do in Arma Reforger?
It writes performance statistics to the log at an interval you give in milliseconds, including FPS, frame time, memory, and the number of players, AI, vehicles and projectiles.
Can I add my own startup parameters on ChicagoServers?
Parameters that have a field on the Startup tab can be set there. For any other parameter, contact support: the launch line and Extra launch options are staff-only.
Does a startup parameter override the server config?
Some do. -bindIP and -bindPort override the bind settings, -AILimit overrides aiLimit, and -disableCrashReporter has the same effect as the config setting. -config is ignored when you launch with -server.
How do I limit AI on an Arma Reforger server?
Set aiLimit in the operating block of the server config, or use the -AILimit parameter, which overrides it. Once the limit is reached, nothing can spawn more AI.