Pattoo ModbusTCP Agent

pattoo_agent_modbustcpd polls data from ModbusTCP enabled systems and reports it to the pattoo server.

Installation

These steps outline what needs to be done to get pattoo_agent_modbustcpd 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_modbustcpd, and all other agents, how to communicate with the pattoo server.
  3. Create a pattoo_agent_modbustcpd.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_modbustcpd 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_modbustcpd client will read its own pattoo_agent_modbustcpd.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_modbustcpd.yaml

Let’s get started on configuring pattoo_agent_modbustcpd.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: TEST 1
    ip_devices:
      - test1.modbus.tcp.device.net
    input_registers:
      - address: 30123
        multiplier: 1
      - 30789
        multiplier: 1
    holding_registers:
      - address: 40123
        multiplier: 1
      - address: 40456
        multiplier: 1
    unit: 0

  - group_name: TEST 2
    ip_devices:
      - test2.modbus.tcp.device.net
    input_registers:
      - 30387
      - 30388
    holding_registers:
      - 40123
      - 40456
    unit: 0

Configuration Explanation

This table outlines the purpose of each configuration parameter

Section Sub-Section Description
polling_interval   The pattoo_agent_modbustcpd 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 Modbus registers
  group_name: Unique name for a group of ip_devices that share the same Modbus parameters. 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.
  ip_devices: List of ip_devices to poll for data
  input_registers: List of Modbus input registers that we need data from for the ip_devices. Each address must be an OID. The multiplier is the value by which the polled data result must be multiplied. The default multiplier is 1.
  holding_registers: List of Modbus holding registers that we need data from for the ip_devices. Each address must be an OID. The multiplier is the value by which the polled data result must be multiplied. The default multiplier is 1.
unit:   Modbus unit number to poll. If not present or blank, the default is ‘0’

Polling

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

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

$ bin/pattoo_agent_modbustcpd.py --help
usage: pattoo_agent_modbustcpd.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_modbustcpd.py --start

Stopping

Stop the daemon using this command.

$ bin/pattoo_agent_modbustcpd.py --stop

Restarting

Restart the daemon using this command.

$ bin/pattoo_agent_modbustcpd.py --restart

Start Polling at Boot

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

Troubleshooting

Troubleshooting steps can be found in the PattooShared troubleshooting documentation