Using OpcCmd Utility as OPC UA PubSub Sniffer: Difference between revisions

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(TBD)
(TBD)
== Capturing message data ==
== Capturing message data ==
(TBD)
In order to display the data captured with each transport message, use the <code>--ShowCaptureData</code> option (shortened: <code>-scd</code>).
Binary data (UADP) are shown in hexadecimal format, textual data (JSON) are decoded first, and shown as strings.  
 
Binary data (UADP) are shown in hexadecimal format, textual data (JSON) are decoded first, and shown as strings.
 
= Typical usage scenarios =
= Typical usage scenarios =
== Show all communication ==
== Show all communication ==

Revision as of 10:08, 15 August 2022

This article assumes that you have basic knowledge of the OPC UA PubSub Sniffing concepts; please read the corresponding article first.

Accessing the OPC UA PubSub Sniffer

In the OpcCmd utility, the OPC UA PubSub Sniffer is accessible as a service under the uaSubscriber command. For interactive usage, you can access it as follows:

uaSubscriber getService uaPubSubSniffer

(shortened: uas gs uapss). You can also use the above command text as a prefix, and append the desired uaPubSubSniffer command at the end, for a "one-shot" execution of the OPC UA PubSub Sniffer.

uaPubSubSniffer subscribeCapture command

(TBD)

Limiting the capture types

(TBD)

Selecting distinct headers

(TBD)

Capturing message data

In order to display the data captured with each transport message, use the --ShowCaptureData option (shortened: -scd).

Binary data (UADP) are shown in hexadecimal format, textual data (JSON) are decoded first, and shown as strings.

Typical usage scenarios

Show all communication

(TBD)

Show all communication with UDP transport mapping:

subscribeCapture opc.udp://239.0.0.1:4840

Show all communication with MQTT transport mapping:

subscribeCapture mqtt://opcua-pubsub.demo-this.com #

(TBD)

Discover who communicates what

(TBD)

Discover who communicates what with UDP transport mapping:

subscribeCapture opc.udp://239.0.0.1:4840 --CaptureTypes AllPubSubMessages --DistinctHeadersOnly !wait Infinite

Discover who communicates what with MQTT transport mapping:

subscribeCapture mqtt://opcua-pubsub.demo-this.com # --CaptureTypes AllPubSubMessages --DistinctHeadersOnly !wait Infinite

(TBD)

Capture and show message data

In order to view the original messages as they are being communicated on the specified PubSub connection, use the --ShowCaptureData option. In our example, we are not interested in further analysis of the received messages, and we therefore limit the capture to the TransportMessage type, by using the --CaptureTypes option. By removing this option, you can view the captured data together with their analysis as OPC UA PubSub messages.

Capture and show message data with UDP transport mapping:

subscribeCapture opc.udp://239.0.0.1:4840 --CaptureTypes TransportMessage --ShowCaptureData

Capture and show message data with MQTT transport mapping:

subscribeCapture mqtt://opcua-pubsub.demo-this.com # --CaptureTypes TransportMessage --ShowCaptureData

(TBD)

See also

OPC UA PubSub Sniffing concepts

Using OpcCmd Utility as OPC UA PubSub Subscriber