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 Linux and NI Linux Real-Time service always starts with the same command. To configure the service, use login and the environment file. Run login once, also when the environment file holds the connection: login creates the folder of the state file, and the service cannot.

State file

The state file holds the connection parameters that login saves, and the rack key: the key that the Core knows this Driver by.

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

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

The state file holds the password as plain text, and each user of the computer can read and change the file. Give the Driver a user with only the Host role.

To remove the saved login and the rack key, run synnax-driver clear. On the next start, the Driver shows in the devices toolbar as a new Driver. The old entry stays on the Core.

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_USERNAME=driver
SYNNAX_DRIVER_PASSWORD=password
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 and NI Linux Real-Time, 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.

install creates the file. Only root can read it, so edit it and run login as root: with sudo on Linux, 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,
    "username": "driver",
    "password": "password",
    "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. Leave out remote_info, so that the Driver registers with the Core on the first start and saves its rack key in the state file.

Parameters

host= localhost: The host of the Core.
port= 9090: The port of the Core.
username= synnax: The username of the Driver user.
password= seldon: The password of the Driver user.
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.
rack_key= 0: The key that the Core knows this Driver by. With 0, or when the Core has no such key, the Driver registers as a new Driver named after the host name of the computer.
cluster_key= nil UUID: The key of the Core that owns rack_key. When it is not the key of the Core, the Driver ignores rack_key and registers as a new Driver, so set both keys.
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