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There are two configuration pages "History" and "Settings".                                   

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Settings Settings

Settings

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The General Settings tab contains a single Main section.Image RemovedImage Added

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GeneralMain GeneralMain

General - Main

• Enabled
  • Whether or not to enable or disable MQTT Transmission from connecting to the configured MQTT Servers.
    
• Audit Profile
  • Selection of a configured Ignition Audit Profile for Transmission to use.
  • Available in release 4.0.16 and limited to auditing tag writes from MQTT Engine to MQTT Transmission if Validate Security Context is enabled

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Servers Servers

Servers

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The configuration sections available are Main, TLS, Advanced and Advanced. RPC Client Connection

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ServerSettingsMain ServerSettingsMain

Server Settings - Main

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• CA Certification Certificate File
  • CA Certification Certificate file currently in use.
• Client Certification Certificate File
  • Client Certification Certificate file currently in use.
• Client Private Key File
  • Client Private Key file currently in use
• Change Password?
  • Check box to enable changing of the optional password.
• Password
  • Optional password associated with the certificate's private key.
• Hostname Verification
  • Enable TLS Hostname Verification. This is true by default.
• TLS ALPN Extensions
  
  • Optional TLS ALPN Extensions to use with this connection

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ServerSettingsAdvanced ServerSettingsAdvanced

Server Settings - Advanced

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• Client ID

  • Optional MQTT client ID to use.  If specified this will be used in the MQTT Transmission connect packet when connecting to the server.  If left blank, a random client ID will be create of the form 'IgnitionTargetMT-xxxxxxxx-xxxx-xxxx'.

    Warning
    Caution: MQTT Clients IDs must be unique and if two clients attempt to connect with the same client ID, one will be forcefully disconnected from the server to allow the other client to connect.

    
    

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  Keep Alive Keep Alive

  Keep Alive
  • The maximum interval in seconds (05-65,535) between any two MQTT protocol control packets sent by the client to the server.
  • Setting the Keep Alive to 0 will disable the Keep Alive functionalityThe minimum Keep Alive for MQTT Transmission is 5.
  • If the client is idle and has no control packets to send, it will send PINGREQ protocol packet and the server is required to respond with a PINGRESP packet. If no response is received from the server within 1.5 times the Keep Alive, the client will close the connection.

  • If the server does not receive, at minimum, a PINGREQ message from a client within 1.5 times the Keep Alive, it will terminate the connection and send the client's LWT if it has been defined.

  • For MQTT Transmission, this is an DEATH message.

• Random Startup Delay
  • The Random Startup Delay in milliseconds of the form 'min-max' where min is the low end and max is the high end of the random range. e.g. '10-1000'. 
• Reconnect Delay
  • The clients reconnect delay in millisecond.
  Auto-reconnect RPC Client
• Subscribe to Legacy STATE Topic
  
  • Allow the RPC Client to auto connect and reconnect when publishing from Ignition Python scripts.Transmission Client to subscribe to a legacy state topic (eg. STATE/IamHost) for primary host ID notifications (available from release 4.0.16)
  • Review Changes to the STATE messages in the Sparkplug v3.0.0 Specification
• Data Format Type
  • The
  Data Format Type
  • The format of the data to send. Default is Sparkplug_B_v1_0_Protobuf with JSON as an option.

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ServerSettingsRPCClient

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ServerSettingsRPCClient

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This tab provides a list of the certificate or private key files if loaded and available for TLS configuration.

The Certificates tab contains a single Main section.

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• Certificate File Upload
  • Browse to the certificate file or private key to upload.
• Friendly Name
  • The friendly name of the certificate file or private key.
• File Description
  • The description of the certificate file or private key.

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Sets

The Sets tab contains a list of server sets.  Each set represents a logical grouping of MQTT servers.  When a set is referenced by a Transmitter configuration, a single connection to one of the servers in the set will be maintained. The other servers will act as failover in the case that a connection with the first is lost.  Server sets cannot have common elements meaning that a single MQTT server cannot be in more than one set.Image Removed

The Sets tab contains a single Main section.

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• This is the friendly name of the set used to easily identify it.

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• This is a friendly description of the set.
  

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• The primary host ID to use for 'state' notifications.
• If configured, MQTT Transmission will subscribe on 'state' notification topics. If MQTT Transmission is notified that the primary backend application has gone 'offline', it will close it's client connection with the MQTT server and walk to the next MQTT server defined in the set.  If the primary host ID is not set, MQTT Transmission will not subscribe on the notification topics and not receive any 'state' notifications.
• This must contain only letters, numbers, or any of the following special characters: . $ % @ ! - _ ^ *

Server Settings - RPC Client Connection

This section was added in release 4.0.18

Previously configuration for the Auto-reconnect RPC Client property was under the Advanced section  

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• Enable/disable RPC Client
  • Enable or disable the RPC MQTT Client 

  • The RPC MQTT Client is used for MQTT publishing from Transmission using Ignition Python scripts

• Auto-reconnect RPC Client
  • If checked, the RPC client will automatically reconnect to the server.
  • If unchecked, the RPC client will try to connect at publish time
• RPC Client ID
  • A manually configured MQTT Client ID for this RPC connection
  • Do not use this setting unless it is an absolute requirement that a specific Client ID be used for the connection to the MQTT Server. If left blank, one will be auto-generated. 
• Username
  • Optional username for this RPC connection if required by the MQTT Server
• Password
  • Optional password for this RPC connection if required by the MQTT Server
• CA Certification File
  • CA Certificate file currently in use
• Client Certificate File
  • Client certificate file currently in use
• Client Private Key File
  • Client private key file currently in use
• Password
  • Optional password associated with the certificates private key
• Hostname Verification
  • Enable hostname verification. Enabled by default
• TLS ALPN Extensions
  • Optional TLS ALPN Extensions to use with this connection

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ServerCertificates ServerCertificates

Servers - Certificates

This tab provides a list of the certificate or private key files if loaded and available for TLS configuration.

The Certificates tab contains a single Main section.

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ServerCertificatesMain ServerCertificatesMain

Server Certificates - Main

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• Certificate File Upload
  • Browse to the certificate file or private key to upload.
• Friendly Name
  • The friendly name of the certificate file or private key.
• File Description
  • The description of the certificate file or private key.

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Sets Sets

Sets

The Sets tab contains a list of server sets.  Each set represents a logical grouping of MQTT servers.  When a set is referenced by a Transmitter configuration, a single connection to one of the servers in the set will be maintained. The other servers will act as failover in the case that a connection with the first is lost.  Server sets cannot have common elements meaning that a single MQTT server cannot be in more than one set.Image Added

The Sets tab contains a single Main section.

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SetsMain SetsMain

Sets - MainImage Added

• Name
  • This is the friendly name of the set used to easily identify it.
• Description
  • This is a friendly description of the set.
    

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  PrimaryHost PrimaryHost

  Primary Host ID
  
  • The primary host ID to use for 'state' notifications.
  • If configured, MQTT Transmission will subscribe on 'state' notification topics. If MQTT Transmission is notified that the primary backend application has gone 'offline', it will close it's client connection with the MQTT server and walk to the next MQTT server defined in the set.  If the primary host ID is not set, MQTT Transmission will not subscribe on the notification topics and not receive any 'state' notifications.
  • This must contain only letters, numbers, or any of the following special characters: . $ % @ ! - _ ^ *

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Transmitters Transmitters

Transmitters

Transmitters are the agents within MQTT Transmission that monitor tags, convert them to Sparkplug Messages, and publish them to an MQTT Server. Each transmitter is configured with a server Set and will attempt to maintain an MQTT client connection with one server in that Set at all times.

Transmitters will monitor tags from a specific Tag Provider and, optionally, a specific Tag Path. If the tag folder hierarchy has been constructed as Group ID, Edge Node ID, and Device ID, then these will automatically be used when building up the MQTT message payload that will represent the Tags as follows:

[TagProvider]<TagPath>/<GroupID>/<EdgeNodeID>/<DeviceID>

If your tag folder hierarchy does not conform to this structure, you can explicitly define these required elements under theSparkPlug Settings section and the elements will be prepended to your tag string.Image Added

The configuration sections available are Tag Settings, Command Settings, History Settings, Alarm Settings, Sparkplug Settings and Advanced Settings.

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TransmittersTagSettings TransmittersTagSettings

Transmitters - Tag Settings

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• Name
  • Unique name for the Transmitter
• Enabled
  • Checkbox to enable/disable the Transmitter. Selected by default.
• Tag Provider
  
  • The name of the tag provider that Transmission will monitor.  By default this is the Ignition 'default' provider.
• Tag Path
  • Optional path to the root folder where the tag tree starts.
  • Transmitters also support a multi-tag path configuration. Reference the Transmitters with Multi-Tag Paths tutorial for configuration assistance.
• Tag Pacing Period
  
  • The buffer period for outgoing Transmission messages in milliseconds.  The default is 1000ms.  This means when a tag change event is detected 1000ms will elapse before an MQTT message is sent.  This allows additional tag change events to be buffered and put into the message and in turn reduce the number of generated MQTT messages.
• Set
  • The Set that the default MQTT Transmission client will connect to.
• Discovery Delay
  • An optional startup delay, in milliseconds, to wait before scanning for Tags to monitor. This is useful when Tags are dynamically created on initial startup, as is the case when using the MQTT Engine module.
• Aliased Tags
  • Checkbox to enable/disable using aliases for tag names when published data messages as tag values change in order to optimize payload size when publishing data. Not selected by default.
• Compression
  • The algorithm to use to compress payloads before they are published to the MQTT Server.  If 'NONE' is selected then compression is disabled.
• Convert UDTs
  • Checkbox to enable/disable converting UDT members to normal Tags before publishing. If enabled the Tags representing the UDT member will retain their member path prefixed by the UDT Instance name. Selected by default.
• Device level UDTs as Devices
  • Treat 'device level UDTs as Sparkplug devices'. Not selected by default and 'Convert UDTs' must be selected
• Publish UDT Definitions
  • Checkbox to enable/disable publishing UDT Definitions in BIRTH. Selected by default and not editable.
• Optimize UDTs
  • Checkbox to enable/disable optimizing UDT payload sizes in NDATA and DDATA payloads. Selected by default and not editable.

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TransmittersCommandSettings TransmittersCommandSettings

Transmitters - Command Settings

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• Block Commands
  • Checkbox to enable/disable the ability to block commands and tag writes received as messages from the MQTT server. Not selected by default.
• Validate Security Context
  • Checkbox to enable/disable the ability to validate the Security Context in write commands. Not selected by default.
  • Reference the Ignition MQTT Security Context HowTo for additional details on how to use this configuration.
• Security Context Hashing Algorithm
  • The hashing algorithm to use when decrypting the Security Context. Available if "Validate Security Context" is enabled.
• Change Password?
  • Checkbox to allow existing password to be changed
• Password
  
  • The hashing password to use when decrypting the Security Context. Available if "Validate Security Context" is enabled.

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TransmittersHistorySettings TransmittersHistorySettings

Transmitters - History Settings

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Note: Store and Forward does not guarantee all data is stored and forwarded. There are some edge cases that are not currently handled with regard to data loss in the event of connection failures related to MQTT keep alive timeouts. This window of potential missed data can be reduced by decreasing MQTT Transmission and MQTT Engine configurable keep alive timeouts.

• History Store
  • The MQTT Transmission History Store to use with the Default Transmitter.
• Enable History Storage by Default
  • Checkbox to enable/disable store and forward for all tags. Selected by default. 
  • Store and forward controls whether or not a tag is stored in the configured History Store when Transmission is offline. To override the global setting,individual tags will require a custom tag property 'StoreAndForward' (type: boolean) to be created and set to the reverse state of the global setting.
• In-Order History
  • Checkbox to enable/disable the flush history in-order (synchronously) before live data resumes. Not selected by default.

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TransmittersAlarmSettings TransmittersAlarmSettings

Transmitters - Alarm Settings

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• Alarm Event Enable

  • When enabled and alarms are enabled on tags, the contents of the triggered alarms will be transmitted via Sparkplug to MQTT Engine and will be inserted into the Ignition Alarm Journal on the server where MQTT Engine is installed.

    Note
    This is not full alarm support as the ability to clear or ack an alarm from MQTT Engine is not currently supported

    
    

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TransmittersSparkplugSettings TransmittersSparkplugSettings

Transmitters - Sparkplug Settings

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• Group ID
  • An ID representing a logical grouping of MQTT Edge Of Network (EoN) Nodes and Devices into the infrastructure.
• Edge Node ID
  • An ID that uniquely identifies the MQTT Edge Of Network (EoN) Node within the infrastructure.
• Device ID
  • An optional ID that uniquely identifies a Device within the infrastructure.

Note that if a 'Device ID' is not specified, any folder within the folder specified by the Tag Path will be considered a device folder and any Tags within it will be published as device Tags. 

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TransmittersAdvancedSettings TransmittersAdvancedSettings

Transmitters - Advanced SettingsImage Added

• Filtered Properties
  • A semicolon delimited list of Tag properties to filter/block from being published

  • By default the filtered properties list contains: 

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    accessRights;clampMode;deadband;deadbandMode;formatString;historicalDeadband;

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Transmitters are the agents within MQTT Transmission that monitor tags, convert them to Sparkplug Messages, and publish them to an MQTT Server. Each transmitter is configured with a server Set and will attempt to maintain an MQTT client connection with one server in that Set at all times.

Transmitters will monitor tags from a specific Tag Provider and, optionally, a specific Tag Path. If the tag folder hierarchy has been constructed as Group ID, Edge Node ID, and Device ID, then these will automatically be used when building up the MQTT message payload that will represent the Tags as follows:

[TagProvider]<TagPath>/<GroupID>/<EdgeNodeID>/<DeviceID>

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The configuration sections available are Tag Settings, Command Settings, History Settings, Sparkplug Settings and Advanced Settings.

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• Name
  • Unique name for the Transmitter
• Enabled
  • Checkbox to enable/disable the Transmitter. Selected by default.
• Tag Provider
  
  • The name of the tag provider that Transmission will monitor.  By default this is the Ignition 'default' provider.
• Tag Path
  • Optional path to the root folder where the tag tree starts.
  • Transmitters also support a multi-tag path configuration. Reference the Transmitters with Multi-Tag Paths tutorial for configuration assistance.
• Tag Pacing Period
  
  • The buffer period for outgoing Transmission messages in milliseconds.  The default is 1000ms.  This means when a tag change event is detected 1000ms will elapse before an MQTT message is sent.  This allows additional tag change events to be buffered and put into the message and in turn reduce the number of generated MQTT messages.
• Set
  • The Set that the default MQTT Transmission client will connect to.
• Discovery Delay
  • An optional startup delay, in milliseconds, to wait before scanning for Tags to monitor. This is useful when Tags are dynamically created on initial startup, as is the case when using the MQTT Engine module.
• Aliased Tags
  • Checkbox to enable/disable using aliases for tag names when published data messages as tag values change in order to optimize payload size when publishing data. Not selected by default.
• Compression
  • The algorithm to use to compress payloads before they are published to the MQTT Server.  If 'NONE' is selected then compression is disabled.
• Convert UDTs
  • Checkbox to enable/disable converting UDT members to normal Tags before publishing. If enabled the Tags representing the UDT member will retain their member path prefixed by the UDT Instance name. Selected by default.
• Device level UDTs as Devices
  • Treat 'device level UDTs as Sparkplug devices'. Not selected by default and 'Convert UDTs' must be selected
• Publish UDT Definitions
  • Checkbox to enable/disable publishing UDT Definitions in BIRTH. Selected by default and not editable.
• Optimize UDTs
  • Checkbox to enable/disable optimizing UDT payload sizes in NDATA and DDATA payloads. Selected by default and not editable.

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• Block Commands
  • Checkbox to enable/disable the ability to block commands and tag writes received as messages from the MQTT server. Not selected by default.
• Validate Security Context
  • Checkbox to enable/disable the ability to validate the Security Context in write commands. Not selected by default.
  • Reference the Ignition MQTT Security Context HowTo for additional details on how to use this configuration.
• Security Context Hashing Algorithm
  • The hashing algorithm to use when decrypting the Security Context. Available if "Validate Security Context" is enabled.
• Change Password?
  • Checkbox to allow existing password to be changed
• Password
  
  • The hashing password to use when decrypting the Security Context. Available if "Validate Security Context" is enabled.

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Note: Store and Forward does not guarantee all data is stored and forwarded. There are some edge cases that are not currently handled with regard to data loss in the event of connection failures related to MQTT keep alive timeouts. This window of potential missed data can be reduced by decreasing MQTT Transmission and MQTT Engine configurable keep alive timeouts.

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• The MQTT Transmission History Store to use with the Default Transmitter.

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• Checkbox to enable/disable the flush history in-order (synchronously) before live data resumes. Not selected by default.

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• Group ID
  • An ID representing a logical grouping of MQTT Edge Of Network (EoN) Nodes and Devices into the infrastructure.
• Edge Node ID
  • An ID that uniquely identifies the MQTT Edge Of Network (EoN) Node within the infrastructure.
• Device ID
  • An optional ID that uniquely identifies a Device within the infrastructure.

Note that if a 'Device ID' is not specified, any folder within the folder specified by the Tag Path will be considered a device folder and any Tags within it will be published as device Tags. 

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• Filtered Properties
  • A semicolon delimited list of Tag properties to filter/block from being published

  • By default the filtered properties list contains: 

    Code Block

    accessRights;clampMode;deadband;deadbandMode;formatString;historicalDeadband;historicalDeadbandMode;historicalDeadbandStyle;historyEnabled;historyMaxAge;historyMaxAgeUnits;historyProvider;historySampleRate;historySampleRateUnits;historyTagGroup;historyTimeDeadband;historyTimeDeadbandUnits;opcItemPath;opcServer;permissionModel;rawHigh;rawLow;sampleMode;scaleFactor;scaleMode;scaledHigh;scaledLow;tagGroup;valueSource;expression;expressionType;ConfiguredTagPath;eventScripts;readPermissions;writePermissions;eventScripts;parentEnabled;sourceTagPath

    
    

  • Tag properties are only published if different from the default Ignition tag property settings and are only published in BIRTH messages.
• Rebirth Debounce Delay
  • The amount of time, in milliseconds, to delay before processing Rebirth NCMD requests after one has been processed. Default of 5000 milliseconds.Default of 5000 milliseconds.
• Include Sparkplug DataTypes
  • Whether or not to include Sparkplug DataTypes for Metrics in Sparkplug DATA payloads
  • Enabled by default

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Records Records

Records

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The configuration sections available are Tag Settings, Sparkplug Settings, Records Signature and Advanced Settings.

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RecordsTagSettings RecordsTagSettings

Records - Tag Settings

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• Group ID
  • The Group ID that matches an existing Sparkplug Edge Node.
• Edge Node ID
  • The Edge Node ID that matches an existing Sparkplug Edge Node.
• Device ID
  • The Device ID that matches an existing Sparkplug Edge Node. (Optional)

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RecordsRecordsSignature RecordsRecordsSignature

Records - Records Signature

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• Enable Signature
  • Checkbox to enable a digital signature field on all Records. Default is de-selected
• Algorithm
  • The hashing algorithm to use when generating the digital signature
  • Options are SHA_1,SHA_224,SHA_256,SHA_384 and SHA_512
• Password
  
  • The password used to generate the PBE secret key for encrypting the digital signature 
• Group ID
  • The Group ID that matches an existing Sparkplug Edge Node.
• Edge Node ID
  • The Edge Node ID that matches an existing Sparkplug Edge Node.
• Device ID
  • The Device ID that matches an existing Sparkplug Edge Node. (Optional)

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RecordsAdvancedSettings RecordsAdvancedSettings

Records - Advanced Settings

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• Enable Auto-Publish
  • Checkbox to enable/disable auto-publish of files. Not selected by default.
  • When set to enable, any new files identified in directory specified in the 'Publish File Path' tag will automatically be published will automatically be published 
  • If set to disabled for manual publish of files, Primary Host ID must be configured for MQTT Transmission and MQTT Engine
• File Scan Rate
  • The rate to scan the files directory specified in the 'Publish Files Path' tag for files to publish. Default is 60 seconds.
• File Scan Rate Time Unit
  • Time unit for 'File Scan Rate' parameter. Default is SECONDS
  • Options are: MILLISECONDS, SECONDS, MINUTES, HOURS and DAYS

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• Group ID
  • The Group ID that matches an existing Sparkplug Edge Node. Cannot be NULL
• Edge Node ID
  • The Edge Node ID that matches an existing Sparkplug Edge Node. Cannot be NULL
• Device ID
  • The Device ID that matches an existing Sparkplug Edge Node. (Optional).

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• Message Size
  • Number of bytes to transfer in one message, Default 1000 bytes.
• Message Pacing Period
  • Message Pacing Period is milliseconds. Default 1000 milliseconds.
• Message ACK Timeout
  • Message acknowledgement timeout in seconds. Default 10 seconds.
• Number Retries
  • Number of retries to publish a file or chunk or a file
• Submit Basic File Attributes
  • Checkbox to enable/disable the basic file attributes to be included in the metrics. Not selected by default.

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The "History" page allows for the configuration of MQTT Transmission History Stores.  In the event that a Transmitter loses its connection with the MQTT Server and is unable to reconnect, a History Store (if enabled) will store all messages corresponding to change events on the monitored tags.  Once a connection with an MQTT server is reestablished the History Store will publish the stored messages with a flag set to indicate that the messages are "historical" to prevent confusion with live data values.Image Removed

The History tab contains a single Main section.

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• • is milliseconds. Default 1000 milliseconds.
• Message ACK Timeout
  • Message acknowledgement timeout in seconds. Default 10 seconds.
• Number Retries
  • Number of retries to publish a file or chunk or a file
• Submit Basic File Attributes
  • Checkbox to enable/disable the basic file attributes to be included in the metrics. Not selected by default.

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History History

History

The "History" page allows for the configuration of MQTT Transmission History Stores.

When a Transmitter is configured to use an MQTT Transmission History Store, data is written to the History Store once MQTT Transmission has determined that there is a connection failure. Once a connection with an MQTT server is re-established the History Store will publish the stored messages with a flag set to indicate that the messages are "historical" to prevent confusion with live data values. Determination of a connection failure can be up to 1.5 times the configured keep alive. and, as such, any data published during this time can be lost.

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The History tab contains a Main section and an Advanced section.

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HistoryMain HistoryMain

History - Main

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• Name
  • The name of the History Store.
• Enabled
  
  • Checkbox to enable/disable the History Store. Not selected by default.
• Type
  • The type of History Store.
  • Data stored in an In-Memory History Store will not be persisted across a module configuration change, module disable/enable, module restart or power loss. 
  • Data stored in a Disk-Backed History Store will persist across a module configuration change, module disable/enable, module restart or power loss.
• History Max Age
  
  • Maximum number of minutes to store history before dropping the data.
• Flush Quantity
  • The maximum number of tags to publish in a single message upon reestablishing communication.
• Flush Period
  • The period to wait in milliseconds between publishes when flushing messages upon reestablishing communication

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HistoryAdvanced HistoryAdvanced

History - Advanced

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• Enable Rolling History Buffer
  • Enable/disable storing data in a rolling buffer to cover data loss in Keep Alive timeout scenario
• Rolling History Prune Interval
  • The interval, in seconds at which to attempt to prune the rolling history buffer
• Rolling History Max Age
  • The maximum age allowed of data, in seconds, in the rolling history buffer
  • This should be at least 2 x the Keep Alive timeout

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• Name
• • The name of the History Store.
• Enabled
  
  • Checkbox to enable/disable the History Store. Not selected by default.
• Type
  • The type of History Store.
  • Data stored in an In-Memory History Store will not be persisted across a module disable/enable, module restart or power loss. 
  • Data stored in a Disk-Backed History Store will persist across a module disable/enable, module restart or power loss.
• Edge Node Tag Capacity
  • Maximum number of Edge Node level tag change events to store per Edge Node before dropping oldest historical Edge Node tag change events. This value is independent of the 'Device Tag Capacity' and only applies to how many 'Edge Node level' tag change events are stored per Edge Node.
  • A tag change event is triggered by either a change in value or quality and results in the tag's Qualified Value (which has three attributes of value, quality and timestamp) being stored. 
• Device Tag Capacity
  
  • Maximum number of Device tag change events to store per Device before dropping oldest historical Device tag change events. This value is independent of the 'Edge Node Tag Capacity' and only applies to how many 'Device level' tag change events are stored per Device.
  • A tag change event is triggered by either a change in value or quality and results in the tag's Qualified Value (which has three attributes of value, quality and timestamp) being stored.
• Flush Quantity
  • The maximum number of tags to publish in a single message upon reestablishing communication.
• Flush Period
  • The period to wait in milliseconds between publishes when flushing messages upon reestablishing communication