Enterprise

Configure a standalone Driver

Set the connection, task, and integration parameters of a standalone Driver with its state file, a configuration file, environment variables, or flags.

A standalone Driver reads its parameters from five sources. A source higher in the list overrides the sources below it:

Command line flags. See the CLI reference.
Environment variables.
A configuration file.
The state file, which synnax-driver login writes.
The defaults.

The parameter flags and the configuration file apply only to synnax-driver start --standalone. The service always starts with the same command. To configure the service, use login and, except on Windows, the environment file. On Linux, run login once, also when the environment file holds the connection: login creates the state file, and the service user cannot.

State file

The state file holds the connection parameters and the API key that login saves. Only its owner and the administrators can read it. On Windows and macOS, while the service is installed, every command uses the path of the computer, so run each command with admin rights. Without the service, commands use the path of the user.

Operating system	Path
Linux, NI Linux RT	`/var/lib/synnax-driver/persisted-state.json`
Windows, service	`C:\ProgramData\synnax-driver\persisted-state.json`
Windows	`%LOCALAPPDATA%\synnax-driver\persisted-state.json`
macOS, service	`/Library/Application Support/synnax-driver/persisted-state.json`
macOS	`~/Library/Application Support/synnax-driver/persisted-state.json`

install moves the login and the OPC UA certificates in the path of the user to the path of the computer, when the path of the computer holds no login yet.

The --state-file flag of start --standalone, login, and clear sets a different path. The service always uses the default path.

To remove the saved login, run synnax-driver clear. Run login again before the next start.

Environment variables

The Driver reads each parameter from a variable named SYNNAX_DRIVER_ and the key in upper case. The integrations have no variable.

SYNNAX_DRIVER_HOST=10.0.0.45
SYNNAX_DRIVER_PORT=9090
SYNNAX_DRIVER_API_KEY=syk_...
SYNNAX_DRIVER_SECURE=false
SYNNAX_DRIVER_CORRECT_SKEW=true
SYNNAX_DRIVER_OP_TIMEOUT=60
SYNNAX_DRIVER_POLL_INTERVAL=1
SYNNAX_DRIVER_SHUTDOWN_TIMEOUT=30
SYNNAX_DRIVER_WORKER_COUNT=4

To learn what each parameter does, see Parameters.

Environment file

On Linux, NI Linux Real-Time, and macOS, the service and login read /etc/synnax/driver.env. Write one KEY=value on each line, with no export. login uses the file only for variables such as GRPC_DEFAULT_SSL_ROOTS_FILE_PATH. It does not read the SYNNAX_DRIVER_ variables. On macOS, login reads the file only while the service is installed.

install creates the file. Only root can read it, so edit it and run login as root: with sudo on Linux and macOS, and as admin on NI Linux Real-Time. Restart the service after you edit the file.

start --standalone does not read the file. For a Driver in a terminal, export the variables in the shell:

export SYNNAX_DRIVER_WORKER_COUNT=8
synnax-driver start --standalone

Configuration file

Give a JSON file to start --standalone with the --config flag. Each key is optional. The file cannot hold comments.

{
  "connection": {
    "host": "10.0.0.45",
    "port": 9090,
    "api_key": "syk_...",
    "secure": false
  },
  "timing": {
    "correct_skew": true
  },
  "manager": {
    "op_timeout": 60,
    "poll_interval": 1,
    "shutdown_timeout": 30,
    "worker_count": 4
  },
  "integrations": ["arc", "ethercat", "http", "labjack", "modbus", "ni", "opc"]
}

The integrations list replaces the default list.

A Driver with no API key logs in once with username and password, creates a rack and its API key, and saves the key in the state file. An upgraded Driver that saved a rack before does this at its first start and keeps its rack. If that user cannot create racks, the Driver keeps logging in with the password and tries again at each start. Once a key is saved, the Driver ignores a username and password and logs a warning.

Parameters

host= localhost: The host of the Core.
port= 9090: The port of the Core.
api_key= "": The API key of the Driver’s rack. The Driver logs in as that rack.
username= synnax: The username to log in with once, to create a rack and its API key. Ignored when an API key is set.
password= seldon: The password to log in with once, to create a rack and its API key. Ignored when an API key is set.
secure= false: Connect to the Core over TLS.
correct_skew= true: Keep the timestamps of hardware-timed NI and LabJack reads in step with the clock of the computer.
op_timeout= 60: The number of seconds after which a task operation that has not finished, such as a start, gives the task the error operation timed out.
poll_interval= 1: The number of seconds between two checks for task operations that have not finished.
shutdown_timeout= 30: The number of seconds that the Driver waits for task operations when it stops.
worker_count= 4: The number of threads that run task operations. Use a value from 1 to 64.
integrations= all: The device integrations to run: arc, ethercat, http, labjack, modbus, ni, and opc. NI Linux RT has no modbus.

For a boolean environment variable, use true or false.

Install

CLI reference