Add admins to your Arma Reforger server with config.json

Add the player’s identity ID to game.admins in config.json, restart, and they are an admin. A player who is not on the list can type #login and the admin password in chat to be an admin until they leave. The list takes up to 30 IDs.

You can use either route, or both. The list is for your regular staff. The password is for a one-off helper.

Get the ID first

Ask each future admin for their identity ID, and paste it exactly. Here is how to find it. The list also accepts Steam IDs. Only admins listed by identity ID skip the join queue, so use the identity ID. A console player has no Steam ID: use the identity ID the server log shows when they join.

In the ArthOS panel

Open your server and the Config Editor tab.
Under Server, set Admin password (1). It cannot contain spaces.

The Server group of the Config Editor with the Admin password row and the Save button — Set the admin password
Save

Under Players, find Admins (1). Type the IDs separated by commas.

The Admins box, which reads "Add one, or paste several" and counts 0 of 30 — Add the admin IDs, up to 30

Choose Save (2 in the first picture). The change applies at the next restart. A restart disconnects everyone who is playing, so you can save now and restart when the server is quiet.

The list takes up to 30 IDs. Bohemia’s documentation still says 20, but a server uses all 30.

If you run the Server Admin Tools mod, its Admin Tools tab has its own Admins and Game Masters lists. Those are separate from game.admins: they make players admins or Game Masters when they join, and apply at the next restart.

For how admins skip the queue, see the join queue. For what each admin list grants, see Game Master and admin permissions.

By hand

Edit config.json and add the IDs to the admins array inside the game block:

{
  "game": {
    "passwordAdmin": "a-long-secret-without-spaces",
    "admins": [
      "11111111-1111-1111-1111-111111111111",
      "76561198000000000"
    ]
  }
}

Keep every other setting that is already in the file. Save, then restart the server. The first value above is an example identity ID, and the second an example Steam ID.

Log in as admin

Join the server.
Open the in-game chat and type #login. A player listed in admins needs no password.
Anyone else types #login <passwordAdmin>, for example #login a-long-secret-without-spaces.
Type #roles to check which server roles you hold. Use #logout to leave admin.

Bohemia says a logged-in admin can use #restart, #shutdown, #kick, #ban, #id and #players. See the admin commands.

Remove an admin

Delete the ID from the list, save and restart. If they knew the admin password, change passwordAdmin too, or they can still log in.

If it does not work

#login says the password is wrong. Check passwordAdmin has no spaces and that you restarted after saving.
A listed player is not an admin. Check the ID has no stray spaces, and that the list holds no more than 30 IDs. Copy the ID again from the log.
The server will not start after a hand edit. A missing comma or an extra comma after the last entry breaks the JSON. Undo the edit, or use the Config Editor, which writes valid JSON.
An admin still waits in the queue. Only IDs given as identity IDs skip it, not Steam IDs.

More on the game: Arma Reforger servers.

Sources: Bohemia wiki: Server Config, Bohemia wiki: Server Management, reforger.armaplatform.com: News

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