The Sender service is responsible for sending data to the local or remote Receiver which, in turn, hands it off to the Historian to be stored. In the event that the Sender cannot connect to the Receiver service, the Sender will buffer the data, caching it to disk. You will notice the 'Buffer' count on the tile will begin to increase. Once the connection is reestablished, the buffered data will flush and data logging can resume.

A Sender is used in tandem with any one of Canary's Collectors (OPC DA/UA, MQTT, SQL, Cygnet, CSV) as well as the Calculation service. It is also needed when using the Write API (i.e. Ignition module).

Status Screen

The 'Status' screen displays all of the current Sender sessions.

• PURGE - clicking this can cause loss of data. If the buffered data in the Sender is no longer wanted, select a session and click the 'PURGE' button. A confirmation dialog displays to force the session to close and delete all buffered data.
  

SESSIONS

• Session - a unique session name made up of the destination computer and log session name
• State
  • Active - Sender is connected to Receiver and transferring data
  • Inactive - connected but has not received data from Collector in the last 5 minutes
  • Connecting attempt # - the Sender will try to make connection with a Receiver every 5 seconds
  • Waiting (send tags) - the Sender is limiting how many tags to connect at one time so as not to overload the system
  • Waiting (buffered data) - buffered data in another session must complete before this session can send data
  • Waiting (timeout) - a timeout has occurred waiting for a response from the Receiver
  • Forward failed - data was sent to the Receiver but the confirmation of receipt was not returned
  • Reconnect - a Receiver service is not available. Possibly the service is stopped or does not exist.
• Connected - Date/Time when the session last made connection with the Receiver or disconnected
• Tags - total tags included in the session
• Store/Sec - TVQs per second being written to the Sender buffer
• Send/Sec - TVQs per second being sent to a Receiver
• TVQs - TVQs currently stored in the Sender buffer
• Properties - tag properties currently stored in the Sender buffer
• Annotations - annotations from a custom sender client (Write API) currently stored in the Sender buffer
• Error Count - number of errors logged since the session was created
• Last Error - the last Sender error logged to the Message log for each session

Configuration Screen

Credentials

These credentials are used to identify the Sender service when connecting securely to the NET.TCP - Username endpoint (55256) on a remote Receiver. In almost all cases, the 'Identity' option is sufficient for sending data. The 'User' option can be used in a multi-tenant environment in which admins may need to restrict clients to writing to a particular DataSet. In this case, security should be enabled in the Views tile and the user defined here in the Sender would need ReadWrite permissions to that specific DataSet. (See Configuring Data Access Security and Permissions)

• Identity
  • Identity - the machine name of the Sender
  • GUID - a unique string value assigned to the Sender client
• User
  • User/Password - the credentials of a user account the Sender will impersonate when connecting to the Receiver

Endpoints

• Net.Pipe - Anonymous (Local Only) - anonymous pipes provide interprocess communication on the local computer. This endpoint is always enabled and is used by local Collectors.
• Net.TCP - Windows (55257) - used for writing data to the historian using the .NET Write API or the Data Entry tool in Axiom
• Https - Username (SOAP) - deprecated
• Http - Anonymous (SOAP) - deprecated
• Https - Username (Web API) (55254) - used for writing data to the historian using the web Write API over a secure connection
• Http - Anonymous (Web API) (55253) - used for writing data to the historian using the web Write API over an anonymous connection

CERTIFICATE (Username)

The configured certificate will be used for making a secure connection over 55254. By default, Canary generates a self-signed certificate, but a trusted certificate can be installed and used in its place if needed.

• Store Name - the file location of the client certificate within the machine's certificate store
• Find Type - criteria by which the Sender searches for the certificate
  • FindBySubjectName
  • FindByThumbprint
• Subject Name - the value of the Subject Name or Thumbprint

Access

The 'Access' screen allows the user to configure who has permission to write data to the historian using the Write API or the Data Entry tool in Axiom.

ALLOW

The 'ALLOW' panel displays the users/groups who granted access to the Sender for writing data to the Historian.

• ADD - click to add users/groups to the 'ALLOW' list

• REMOVE - by selecting an existing user/group from the list a user can remove them from the 'ALLOW' list

DENY

The 'DENY' panel displays the users/groups specifically denied access to connect to the Sender.

• ADD - click to add users/groups to the 'DENY' list

• REMOVE - by selecting an existing user/group from the list a user can remove them from the 'DENY' list