Tutorials and Howto references for Cirrus Link modules and drivers

Architecture Examples

• Getting Started: Two Ignition Architecture
  • A simple architecture showing how MQTT Transmission and MQTT Engine interact via MQTT Distributor in two Ignition instances
• Advanced: MQTT Modules in Redundant Ignition Environment
  • Adding redundancy to MQTT enabled Ignition systems on the edge and at the central gateway
• MQTT IIoT Recipe
  • Recipe tutorial for creating MQTT architectures
• Using MQTT Modules in a UNS Architecture
  • Describes how to use MQTT Transmission and MQTT Engine in a UNS architecture 

General

• Cirrus Link Module Installation
  • Describes the steps for installing the Cirrus Link modules
• Cirrus Link Module Compatibility
  • Describes the modules compatibility with Ignition versions
• Ignition Datatypes Supported via MQTT
  • Describes the Ignition datatypes supported

• Connecting Ignition Modbus TCP to Modbus Serial Devices

  • Describes how to connect Ignitions Modbus TCP driver to Modbus Serial PLCs using a third party gateway

Security (TLS/SSL)

• Secure MQTT Communication using SSL or TLS
  • Overall getting started for securing MQTT communications
• Getting a Certificate from a Certificate Authority
  • General process for getting a certificate from a certificate authority
• Creating and Using an Ignition generated Self-Signed Certificate
  • Process for implementing a self-signed certificate (not recommended for production)
• Using pre-4.0.4 MQTT Modules
  • Using old modules with TLS/SSL
• Configuring the MQTT Modules to use a non Ignition generated Self-Signed Certificate
  • How to configure the MQTT modules for self-signed certs
• How do I find the Self-Signed Certificates loaded for Ignition
  • Process for getting important certificate information when you don't have it

MQTT Modules (General)

• Ignition MQTT Security Context
  • Explains how to allow secure command writes through MQTT Engine to MQTT Transmission by using custom tag permissions to authorize a tag write based on user.
• Secure MQTT Communication using SSL or TLS
  • Explains the configuration required to secure MQTT communication over SSL/TLS
• MQTT Alarms
  • Describes best practices for creating alarms on MQTT tags
• Managing historic data with MQTT Modules
  • MQTT Store and Forward Overview
    • Describes how MQTT Store and Forward allows data to be buffered locally at a client when connections are down to the MQTT Server infrastructure and deliver that data when the connection is restored.
  • MQTT Transmission History Store - Rolling History Buffer
    • Describes how the MQTT Transmission History Store Rolling History Buffer works

  • Determining the settings for an MQTT Transmission History Store

    • Shows how to determine the settings for an MQTT Transmission History Store
  • Minimizing data loss when using MQTT Store and Forward
    • Describes the use of Keep Alive and Primary Host ID within an MQTT Store and Forward system 
  • Configuring history on MQTT Engine tags
    • Details the configuration needed across the MQTT system for historical inserts into Ignition’s Tag Historian Module.
• Connecting to AWS IoT Core
  • Describes how to connect MQTT Engine or MQTT Transmission to Amazon Web Services (AWS) IoT Core.

• Bandwidth Limiting Sparkplug B over Cellular

  • Describes configuration options to reduce the overall bandwidth when using MQTT Modules over a cellular connection
• Changes to the STATE message in the Sparkplug v3.0.0 specification
  • Describes the changes to the STATE message in the Sparkplug v3.0.0 specification and how the modules handle existing v2.0.0 clients
• Sparkplug NCMD or DCMD workflow using MQTT Modules
  • Describes the workflow of command messages from MQTT Engine to MQTT Transmission
• Understanding how tag changes at the Edge affect MQTT Engine
  • Describes how tag changes at the Edge affect MQTT Engine and the actions required to correctly represent the tags at Engine
• Timestamps and the MQTT Modules
  • Describes how a timestamp travels from the PLC to the receiving application through the MQTT Modules
• Cirrus Link Modules Sparkplug message topics and payloads
  • Describes how Cirrus Link modules populate the Sparkplug message topic and payloads

MQTT Distributor

• MQTT Distributor Access Control Lists
  
  • Describes how Access Control Lists (ACLs) control what topics a given username/password pair is allowed to publish and subscribe on.
• Python Scripting
  • Details the API calls available for the MQTT Distributor Module
• MQTT Distributor Tags
  • Describes the tags MQTT Distributor automatically creates for MQTT Distributor control
• MQTT Clients at MQTT Distributor
  • Provides simple scripts to return counts and additional information from MQTT Distributor Tags

MQTT Engine

• Enable Device Writes from Ignition
  • Shows how to enable tag writes for MQTT Engine tags.  These are disabled by default to prevent accidental writes to remote device outputs.
• MQTT Security Context
  • Shows how to configure MQTT Engine and MQTT Transmission to use Ignitions Security Context to validate writes to tags from MQTT Engine to MQTT Transmission.
• MQTT Engine Custom Namespace
  • Shows how to use MQTT Engine Custom Namespaces to provide support for generic, non Sparkplug compliant MQTT messages with string based payloads
  • Managing Ignition timestamps for MQTT data when using custom namespaces
    • Describes how to use the MQTT message's payload timestamp property rather than the time that the message arrives on the broker or received by Ignition
  • Reading bytes from an incoming binary message
    • Describes how to parse MQTT payloads with binary data
  • Writing back to an Edge device from a custom namespace tag
    • Describes how to write back to an Edge device from a custom namespace tag
  • MQTT Engine String Replacement
    • Shows how to determine and configure the replacing of certain characters or strings of characters so the tag path and tag names can be properly created in Ignition.
• MQTT Engine Tag Latching
  • Shows how to configure MQTT Engine for synchronizing events.
• MQTT Publishing via MQTT Engine
  • Explains how to publish messages directly from Ignition Python scripts.
• MQTT Engine Default Namespaces
  • Describes the default namespaces are used to provide support for Sparkplug compliant MQTT messages.
  • Managing Ignition timestamps for MQTT data when using custom namespaces
    • Shows how to use the MQTT message's payload timestamp property for the tag change timestamp.
  • Reading bytes from an incoming binary message
    • Shows how to parse a binary message to extract the bytes
• Python Scripting
  • Details the API calls available for the MQTT Engine Module
• Exposing MQTT Engine as an OPC UA tag provider
  • Shows how to expose MQTT Engine as a OPC UA tag provider
• MQTT Engine Tags
  • Describes the tags MQTT Engine automatically creates for MQTT Engine control
• MQTT Clients at MQTT Engine
  • Provides simple scripts to run in the Ignition script console to display the client count and additional information
• Sparkplug EdgeNodes at MQTT Engine
  • Provides simple scripts to run in the Ignition script console to display the Sparkplug EdgeNode count and additional information
• Filtering or blocking tag properties
  • Describes how published tag properties can be filtered/ignored by Engine
• Custom Properties
  • Describes the custom properties for MQTT Engine
  • allowCustomNamespaces QOS1
    • Shows how to configure MQTT Engine to subscribe on QoS1 for custom namespace topics.
  • reorderingTimeout
    • Shows how to configure MQTT Engine to handle messages from Sparkplug Edge Nodes which are delivered out of order
• Managing historic data with MQTT Modules
  • MQTT Store and Forward Overview
    • Provides an overview of Store and Forward within an MQTT environment
  • MQTT Transmission History Store - Rolling History Buffer
    • Describes how the MQTT Transmission History Store Rolling History Buffer works

  • Determining the settings for an MQTT Transmission History Store

    • Shows how to determine the settings for an MQTT Transmission History Store

  • Minimizing data loss when using MQTT Store and Forward

    • Describes the use of Keep Alive and Primary Host ID by MQTT Transmission and MQTT Engine within a Store and Forward system
  • Configuring history on MQTT Engine tags
    • Describes how to configure MQTT Engine tags to process historical data and insert into Ignitions Tag Historian module 
• Connecting to AWS IoT Core
  • Describes how to connect to AWS IoT Core
• Understanding how tag changes at the Edge affect MQTT Engine
  • Describes how tag changes at the Edge affect MQTT Engine and the actions required to correctly represent the tags at Engine
• Timestamps and the MQTT Modules
  • Describes how a timestamp travels from the PLC to the receiving application through the MQTT Modules
• Cirrus Link Modules Sparkplug message topics and payloads
  • Describes the contents of the Cirrus Link Modules Sparkplug message topics and payloads
• Understanding Servers and Server Sets
  • Describes how servers and sets interact
• Using MQTT Modules in a UNS Architecture
  • Describes how to use MQTT Transmission and MQTT Engine in a UNS architecture 
• What is Primary Host ID and how do I use it
  • Describes Primary Host ID and how to use it

MQTT Transmission

• Sending OPC Tag Data with Transmission
  • Shows how to configure OPC tags to be published from Ignition using MQTT Transmission
• MQTT Publishing via MQTT Transmission
  • Shows how to use scripting in Ignition to publish messages in conjunction with Ignition and MQTT Transmission
• Using MQTT Transmissions 'Refresh' Mechanism
  • Shows how to tell MQTT Transmission to rescan the tag tree to pick up newly added tags
• Transmission Custom Tag Properties
  • Describes the MQTT Transmission custom tag properties.
• User Defined Types (UDTs) within Transmission
  • Shows how UDTs are represented and best practices for managing within Transmission
• Transmitters with Multi-Tag paths
  • Shows how MQTT Transmitters can be configured for multiple providers
• MQTT Transmission Transmitters and Tag Trees
  • Describes how MQTT Transmission Transmitter configurations interact with Ignition tag trees to publish MQTT messages and tags to an MQTT Server
• Python Scripting
  • Details the API calls available for the MQTT Transmission Module
• Filtering or blocking tag properties
  • Describes how tag properties can be filtered/block from being published by Transmission
• MQTT Transmission Tags
  • Describes the tags MQTT Transmission automatically creates for the MQTT Transmission control
• MQTT Clients at MQTT Transmission
  • Provides simple scripts to run in the Ignition script console to display the client count and additional information
• Publishing infrequently changing data from MQTT Transmission
  • Describes how to publish infrequently changing data from MQTT Transmission
• Managing records with MQTT Transmission and MQTT Recorder
  • Shows how to configure the MQTT modules to generate and publish records to be stored in an MySQL database
• Managing files with MQTT Transmission and MQTT Engine
  • Shows how to configure the MQTT modules to publish and process files
• Understanding Servers and Sets
  • Describes how servers and sets interact
• Managing historic data with MQTT Modules
  • MQTT Store and Forward Overview
    • Provides an overview of Store and Forward within an MQTT environment
  • MQTT Transmission History Store - Rolling History Buffer
    • Describes how the MQTT Transmission History Store Rolling History Buffer works

  • Determining the settings for an MQTT Transmission History Store

    • Shows how to determine the settings for an MQTT Transmission History Store

  • Minimizing data loss when using MQTT Store and Forward

    • Describes the use of Keep Alive and Primary Host ID by MQTT Transmission and MQTT Engine within a Store and Forward system

  • Configuring history on MQTT Engine tags

    • Details the configuration for MQTT Engine and MQTT Transmission for historical inserts into Ignition’s Tag Historian Module
• Connecting to AWS IoT Core
  • Describes how to connect AWS IoT Core
• Understanding how tag changes at the Edge affect MQTT Engine
  • Describes how tag changes at the Edge affect MQTT Engine and the actions required to correctly represent the tags at Engine
• Timestamps and the MQTT Modules
  • Describes how a timestamp travels from the PLC to the receiving application through the MQTT Modules
• JSON format published by MQTT Modules 
  • Details the JSON format published by MQTT Modules
• MQTT Security Context
  • Shows how to configure MQTT Engine and MQTT Transmission to use Ignitions Security Context to validate writes to tags from MQTT Engine to MQTT Transmission
• Cirrus Link Modules Sparkplug message topics and payloads
  • Describes the contents of the Cirrus Link Modules Sparkplug message topics and payloads
• Using MQTT Modules in a UNS Architecture
  • Describes how to use MQTT Transmission and MQTT Engine in a UNS architecture 
• What is Primary Host ID and how do I use it
  • Describes Primary Host ID and how to use it
• Which MQTT Transmission Transmitter should I use
  • Describes the differences between MQTT and Sparkplug and when to use the Sparkplug Transmitter or UNS Transmitter 

MQTT Recorder

• Python Scripting
  • Details the API calls available for the MQTT Recorder Module
• MQTT Recorder Tags
  • Describes the tags MQTT Recorder automatically generates for the MQTT Recorder control
• Managing records with MQTT Transmission and MQTT Recorder
  • Shows how to configure the MQTT modules to generate and publish records to be stored in an MySQL database
• MR: How to use and validate the Record Signature
  • Shows how to configure and validate the Record Signature

AWS Injector

• Getting Started: AWS Injector Quick Start
  • Shows end to end configuration of AWS Injector and getting tag data flowing into Kinesis and DynamoDB.
• Connecting Disparate Industrial Systems to AWS using Ignition Edge
  • A tutorial showing how to use Ignition Edge and MQTT Transmission to AWS via AWS Greengrass

• Connecting to AWS IoT Core

  • Describes how to connect MQTT Engine or MQTT Transmission to Amazon Web Services (AWS) IoT Core
• Python Scripting
  • Details the API calls available for the AWS Injector Module
• AWS Custom Tag Properties
  • Details the AWS Injector custom tag properties 
• AWS Injector Tags
  • Describes the tags AWS Injector automatically creates for the AWS Injector connections
• Cloud Injector Tag Agents and Tag Trees
  • Describes how Cloud Injector Agent configurations interact with Ignition tag trees to push messages and tag change events to the cloud service
• Managing UDTs through Injector Tag Agents
  • Describes how the UDT parameters for the Tag Agents affect the message payload
• JSON format published by MQTT Modules 
  • Details the JSON format published by MQTT Modules
• Determining the settings for an Injector History Store
  • Describes how to determine the configuration settings for an Injector History Store
• How the MQTT Injector Push Trigger affects data published
  • Describes how the Push Trigger configuration affects data published

Azure Injector

• Getting Started: Azure Injector Quick Start
  • Shows end to end configuration of Azure Injector and getting tag data flowing into Azure IoT Hub.
• Using IoT Hub Message Based Routing
  • Shows configuration for an Azure Injector module to publish live tag data to an Azure IoT Hub where the messages are then automatically routed and stored in an Azure Storage Container.
• Pushing Data to Azure Time Series Insights
  • Shows configuration for an Azure Injector module to publish live tag data to an Azure IoT Hub configured as a data source form Time Series Insights. Messages are then automatically stored in Time series Insights.
• Publishing Data to Azure IoT Edge
  • Shows how how to make a module connection from the Azure Injector modules to Azure IoT Edge. 
• Publishing Data to Azure IoT Central
  • Shows how to connect and publish live tag data to am Azure IoT Hub.
• Python Scripting
  • Details the API calls available for the Azure Injector Module
• Azure Injector Tags
  • Describes the tags Azure Injector automatically creates for the Azure Injector control
• Azure Custom Tag Properties
  • Describes the Azure Injector custom tag properties
• Increasing throughput for the Azure Injector
  • Describes how to set the Push Policy to utilize multiple endpoints to increase throughput
• Cloud Injector Tag Agents and Tag Trees
  • Describes how Cloud Injector Agent configurations interact with Ignition tag trees to push messages and tag change events to the cloud service
• Managing UDTs through Injector Tag Agents
  • Describes how the UDT parameters for the Tag Agents affect the message payload
• JSON format published by MQTT Modules 
  • Details the JSON format published by MQTT Modules
• Determining the settings for an Injector History Store
  • Describes how to determine the configuration settings for an Injector History Store
• Connecting to Azure IoT Hub with Certificate Based Authentication
  • Describes how to create the device certificates required and how to configure Azure Injector to support certificate based authentication
• How the MQTT Injector Push Trigger affects data published
  • Describes how the Push Trigger configuration affects data published

Google Cloud Injector

• Getting Started: Google Cloud Injector Quick Start
  • A quick start guide to installing and configuring the Google Cloud Injector module to push Tag data to a Cloud IoT Core.
• Python Scripting
  • Details the API calls available for the Google Cloud Injector Module
• Google Cloud Injector Tags
  • Describes the tags Google Cloud Injector automatically creates for the Google Cloud Injector control
• GCI: Custom Tag Properties
  • Describes the Google Cloud Injector custom tag properties
• Cloud Injector Tag Agents and Tag Trees
  • Describes how Cloud Injector Agent configurations interact with Ignition tag trees to push messages and tag change events to the cloud service
• Managing UDTs through Injector Tag Agents
  • Describes how the UDT parameters for the Tag Agents affect the message payload
• Determining the settings for an Injector History Store
  • Describes how to determine the configuration settings for an Injector History Store
• JSON format published by MQTT Modules 
  • Details the JSON format published by MQTT Modules
• How the MQTT Injector Push Trigger affects data published
  • Describes how the Push Trigger configuration affects data published

Driver Modules (General)

• Creating Device Connections with Ignition scripting
  • Shows the driver device connection properties required when created through Ignition scripting
• Publishing data for EFM Modules
  • Shows how to publish data from the EFM Modules

ABB Total Flow Driver

• EFM ABB Totalflow Quickstart
  • Explains setting up the EFM ABB Totalflow driver module and configuring the device connections
• EFM ABB Totalflow Quickstart - Basic AAR Polling
  • Explains setting up the EFM ABB Totalflow driver and configuring the device connections without using Array-Register Definitions
• Sending ABB Totalflow Alarms to a Central Ignition Gateway
  • Explains how to get alarms to the central Ignition gateway.
• Sending ABB Totalflow Events to a Central Ignition Gateway
  • Explains how to get events to the central Ignition gateway.
• Sending ABB Totalflow History to a Central Ignition Gateway
  
  • Explains how to get history to the central Ignition gateway.
• Cloning an ABB Totalflow Device Connection
  • Details scripts to clone an ABB Totalflow Device Connection
• How can I recover a lost ABB record
  • Details how to reset the internal record counters and recover lost records

Emerson ROC Driver

• EFM Emerson ROC Quickstart
  • Explains setting up the EFM Emerson ROC driver module and configuring the device connections
• Sending ROC Alarms to a Central Ignition Gateway
  • Explains how to get alarms to the central Ignition gateway.
• Sending ROC Events to a Central Ignition Gateway
  • Explains how to get events to the central Ignition gateway.
• Sending ROC History to a Central Ignition Gateway
  • Explains how to get history to the central Ignition gateway.

• Emerson ROC Driver Configuration Data Storage

  • Explains where the Emerson ROC Driver configuration is stored
• Tips for debugging Emerson ROC TLP configuration issues
  • Provides tips for debugging Emerson ROC TLP configuration issues 
• Cloning an Emerson ROC Device Connection
  • Details scripts to clone an Emerson ROC Device Connection

Opto 22 groov EPIC and SNAP PAC Driver

• Opto 22 groov EPIC and SNAP PAC Quickstart
  • Explains setting up the Opto 22 groov EPIC and SNAP PAC driver module and configuring the device connections

Ignition Edge IIoT

• Installing Ignition Edge IIoT as a Docker Container
  • Details how to install Ignition Edge IIoT as a Docker Container
• MQTT Transmission Tutorials/Howtos
  
  • Tutorials and howtos covering installation, configurations, and usage of MQTT Transmission
• Emerson ROC Driver Tutorials/Howtos
  • Tutorials and howtos covering installation, configurations, and usage of Emerson ROC Driver
• ABB Totalflow Driver Tutorials/Howtos
  • Tutorials and howtos covering installation, configurations, and usage of ABB Totalflow Driver

AWS Sitewise Engine

IoT Bridge for AWS Sitewise

• IoT Bridge for SiteWise: Quickstart
  
  • A quickstart guide that walks through setup and use of IoT Bridge for SiteWise from edge to cloud
• IoT Bridge for SiteWise: AMI Access Instructions
  

  • Instructions on accessing the IoT Bridge EC2 instance via SSH and files of interest in the IoT Bridge AMI

• IoT Bridge for SiteWise: Mappings and Constraints
  
  • Covers how data is mapped between Inductive Automation's Ignition platform and AWS IoT SiteWise and what rules must be followed
• IoT Bridge for SiteWise: FAQ
  
  • Frequently Asked Questions

IoT Bridge for Azure

• IoT Bridge for Azure: Mappings and Constraints
  • Covers how data is mapped between Inductive Automation's Ignition platform and Azure Digital Twins and what rules must be followed
• IoT Bridge for Azure: Quickstart
  •  A quickstart guide that walks through setup and use of IoT Bridge for Azure from edge to cloud
• IoT Bridge for Azure: Virtual Machine Access Instructions

  • Instructions on accessing the IoT Bridge VM instance via SSH and files of interest in the IoT Bridge AMI

• IoT Bridge for Azure: How to find your Azure Marketplace Billing ID
  • Instructions on how to find your Azure Marketplace Billing ID

IoT Bridge for Snowflake

• IoT Bridge for Snowflake: AWS Quickstart
  • A quickstart guide that walks through setup and use of IoT Bridge for Snowflake from edge to cloud
• IoT Bridge for Snowflake: AWS AMI Access Instructions
  • Instructions on accessing the IoT Bridge EC2 instance via SSH and files of interest in the IoT Bridge AMI

• IoT Bridge for Snowflake: Azure Quickstart
  • A quickstart guide that walks through setup and use of IoT Bridge for Snowflake from edge to cloud
• IoT Bridge for Snowflake: Azure VM Access Instructions
  • Instructions on accessing the IoT Bridge Virtual Machine via SSH and files of interest in the IoT Bridge VM
• IoT Bridge for Snowflake: How to find your Azure Marketplace Billing ID
  • Instructions on how to find your Azure Marketplace Billing ID

Video Reference

Implementing MQTT in Ignition 8

• Video 1: What is MQTT
• Video 2: How MQTT Works
• Video 3: MQTT Sparkplug Specification
• Video 4: MQTT & Ignition
• Video 5: MQTT Distributor Module
• Video 6: MQTT Transmission Module
• Video 7: Using The MQTT Transmission Module to Publish Data
• Video 8: MQTT Engine Module
• Video 9: Allow Outbound Tag Writes
• Video 10: Primary Host ID Setting
• Video 11: How to Set Up Transport Layer Security
• Video 12: Set Up Store-and-Forward System

Troubleshooting Common Issues

• I have data that is toggling between stale and healthy at my subscribing MQTT Client
• I created a Transmitter but my MQTT Transmission module does not show connections to my MQTT Server.
• I made a update to a UDT and now my data is now longer reporting.
• I have Ignition QualityCodes in Cirrus Link module payloads that are not listed in the Ignition documentation.
• I deleted my MQTT Engine tags and lost all alarm and history configuration
• How do I know if my MQTT modules are compatible with my version of Ignition
• Do I need to do anything special to connect to my TTN (www.thethingsnetwork.org) broker
• Why are the parameter labels for the modules displayed oddly in the UI
• How do I exclude tags from being included in Transmission Sparkplug message payload
• How do I exclude tags from being stored in a configured HistoryStore when Transmission is offline
• I have connections to AWS IoT Core toggling between connected and disconnected
• How do I resolve No Meter/Station ID found errors for Emerson ROC
• I have configured SSL but my client is not connecting
• How many simultaneously connected clients does MQTT Distributor support
• Why is my history store flushing slowly and the current live values not being sent
• How can I speed up my file transfer through MQTT Transmission

• How do I check the connection status of my Edge client through tags

• How do I minimize data loss when using MQTT Store and Forward
• How do I resolve out of order messages arriving at MQTT Engine from a server that does not guarantee in order delivery of messages
• How do I configure MQTT engine to subscribe on QOS1 for non Sparkplug messages
• How can I reduce the overall bandwidth when using Ignition and MQTT modules over a cellular connection
• How do I block tag properties from being published by MQTT Transmission
• How do I ignore tag properties at engine that are published by MQTT Transmission
• What is the JSON format published by the Cloud Injector modules
• How do I allow OPC UA clients to access MQTT Engine tags
• How can I synchronize events at MQTT Engine when using tag change scripts
• How do I know how many MQTT clients are connected to MQTT Distributor
• How do I debug the EFM ABB Totalflow 'Failed to set data point' warnings from XRegisterData
• Why are my tag properties not being published by MQTT Transmission
• Why am I getting a certificate expired warning when loading a module?

• I updated MQTT Engine to 4.0.14 or greater and have Edge Clients using pre 4.0.14 modules that do not connect

• Can I connect to Azure Event Grid
• Troubleshooting Azure IoT Hub Connections
• How do I verify history store flushes from MQTT Transmission
• I have missing historical data at my historian
• How do I configure EFM ABB Totalflow to poll specific Holding Registers

• Expected tag change events not being published

• Unable to download or run a scheduled Ignition GWBK

• MQTT Engine certificates fail to load on startup

• What is the difference between a REBIRTH request from MQTT Engine and REFRESH at MQTT Transmission
• Ignition UI is showing Internal error when attempting to access Cirrus Link Module configuration
• How do I resolve a UDT definition collision detected