.orgs.json

{ 
    "remotes": {
        "development": {
            "name": "development",
            "default": false,
            "username": "[your development env username]",
            "password": "[your development env password]",
            "serverUrl": "https://test.salesforce.com"
        },
        "production": {
            "name": "production",
            "default": false,
            "username": "[your production env username]",
            "password": "[your production env password]",
            "serverUrl": "https://login.salesforce.com"
        }
    }
}