Pattoo OPC UA Agents

pattoo_agent_opcuad polls Analog Value data from OPC UA enabled systems and reports it to the pattoo server.

Installation

These steps outline what needs to be done to get pattoo_agent_opcuad working.

  1. Follow the installation steps in the Basic Installation file.
  2. Configure the pattoo.yaml configuration file following the steps in Configuration Guide. This file tells pattoo_agent_opcuad, and all other agents, how to communicate with the pattoo server.
  3. Create a pattoo_agent_opcuad.yaml configuration file. Details on how to do this follow.
  4. Start the desired daemons as explained in sections to follow. You may want to make these systemd daemons, if so follow the steps in the Basic Installation file.

Setting the Configuration Directory Location

pattoo_agent_opcuad is a standard pattoo agent and needs its configuration directory defined by using the PATTOO_CONFIGDIR environmental variable. Here is how to do this from the Linux command line:

$ export PATTOO_CONFIGDIR=/path/to/configuration/directory

pattoo_agent_opcuad client will read its own pattoo_agent_opcuad.yaml configuration file located this directory when PATTOO_CONFIGDIR is set.

You can automatically set this variable each time you log in by adding these lines to your ~/.bash_profile file.

export PATTOO_CONFIGDIR=/path/to/configuration/directory

Make sure that files in this directory are readable by the user that will be running standard pattoo agent daemons or scripts.

Configuring pattoo_agent_opcuad.yaml

Let’s get started on configuring pattoo_agent_opcuad.yaml. Here is a sample of what should be added. An explanation follows.

NOTE: The indentations in the YAML configuration are important. Make sure indentations line up. Dashes ‘-‘ indicate one item in a list of items.

polling_interval: 300

polling_groups:

  - group_name: GROUP 1
    ip_target: server-01.opcua.net
    ip_port: 4840
    username: opcua_username
    password: opcua_password
    nodes:
      - address: ns=1;s=[OPCUA_SERVER_1]DischargehAirTemp.PV

  - group_name: GROUP 2
    ip_target: server-02.opcua.net
    ip_port: 4840
    username: opcua_username
    password: opcua_password
    nodes:
      - address: ns=1;s=[OPCUA_SERVER_2]DischargehAirTemp.PV

Configuration Explanation

This table outlines the purpose of each configuration parameter

Section Sub-Section Description
polling_interval   The pattoo_agent_opcuad will report to the pattoo server every polling_interval seconds
polling_groups:   List of groupings of ip_devices that need data from a shared set of OPC UA nodes. Make this the first entry in the configuration sub-section. Make sure it starts with a dash ‘-‘ which indicates the beginning of a new grouping.
  group_name: Unique name for the set of parameters required to poll an OPC UA ip_device
  ip_device: The ip_device to poll for data
  ip_port: The ip_port on which the ip_device is listening for data
  username: The OPC UA username to use when querying the ip_device
  password: The OPC UA password to use when querying the ip_device
  nodes: OPC UA Analog Value node to poll for data from for the ip_devices. Each address must be a OPC UA node. The multiplier is the value by which the polled data result must be multiplied. This is useful in converting byte values to bits. The default multiplier is 1.

Polling

Use pattoo_agent_opcuad to poll your devices. The daemon has a simple command structure below.

You will need a pattoo_agent_opcuad.yaml configuration file in the PATTOO_CONFIGDIR directory before you start.

$ bin/pattoo_agent_opcuad.py --help
usage: pattoo_agent_opcuad.py [-h] [--start] [--stop] [--status] [--restart]
                         [--force]

optional arguments:
  -h, --help  show this help message and exit
  --start     Start the agent daemon.
  --stop      Stop the agent daemon.
  --status    Get daemon daemon status.
  --restart   Restart the agent daemon.
  --force     Stops or restarts the agent daemon ungracefully when used with --stop or
              --restart.
$

Use these commands for general operation of the daemon.

Starting

Start the daemon using this command.

$ bin/pattoo_agent_opcuad.py --start

Stopping

Stop the daemon using this command.

$ bin/pattoo_agent_opcuad.py --stop

Restarting

Restart the daemon using this command.

$ bin/pattoo_agent_opcuad.py --restart

Start Polling at Boot

Configuration Guide provides information on how to get the pattoo_agent_opcuad daemon to start at boot.

Troubleshooting

Troubleshooting steps can be found in the PattooShared troubleshooting documentation