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  9. Connecting and Disconnecting Problem

Connecting and Disconnecting Problem

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30 Sep 2024 07:29 #13189 by support
Replied by support on topic Connecting and Disconnecting Problem
Hello.

Ad 2. The callback enqueuer overflow means that the code you have for handling the events or callbacks from EasyUAClient does cope fast enough with incoming notifications. It can be fully blocked, or simply slower (on average) than the influx. Over the time, the queue inside inside EasyUAClient fill us, and you then get this error. You need to figure out where and why is your code blocked (or too slow), and fix it.

If you are dealing with large number of items, and this is just a "peak" (which may happen upon initial connection, or as a result of failure disconnection), it may be appropriate to increase the size of the queue. How many items are you subscribing to?

Regarding disconnection: It appears to be a "regular" disconnection, i.e. automatically done when the connection is not needed. The question should first be reversed. Please explain why do you think it is an issue? QuickOPC disconnects when there is no need to be connected. It connects when you make a one-time operation (such as Read), or when you subscribe. It tries to stay connected when subscribed to anything. Are you sure that your code is subscribed to something *at that moment*?

Ad 1. QuickOPC treats the OPC UA DataValue (status code, server and source timestamps, and the actual value) as a single "unit", and passes it without modification (aside from necessary type conversion) from the server to your code. If the server/source timestamp are always so off, you should ask this question at the server side (e.g. the date/time on the server might be set incorrectly). If the timestamps are OK initially and then drift away, it might be because of the same reason described above - the processing code being too slow or blocked, and then - when it unblocks - receiving queued notification that are from rather distant past.

Regards
The following user(s) said Thank You: adaml@trunovate.com

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29 Sep 2024 10:55 #13188 by adaml@trunovate.com
Connecting and Disconnecting Problem was created by adaml@trunovate.com
1. When MonitoredItemChanged event occurs there is a gap of more than a day between
ServerTimestamp, SourceTimestamp
and the current time. Why is this happening?

2. Regarding this log, What and who caused the disconnection, an action of my service or the device? How to deal with a Callback enqueuer overflow problem?
*Disconnecting and connecting happens about every minute
*After restarting the service, the problem is solved

2024-09-26 11:29:18.033 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6018 user token selection on endpoint URL "opc.tcp://127.0.0.1:49320" candidate report (2 entries) follows.
[0:NotEligible(NotApplicable("docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0")), 1:Winner("")].
2024-09-26 11:29:18.033 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6018 on endpoint URL "opc.tcp://127.0.0.1:49320" has been associated with user identity token type 'Anonymous', display name "Anonymous".
2024-09-26 11:29:18.042 – EasyUAClientOnLogEntry Message The OPC-UA server on endpoint URL "opc.tcp://127.0.0.1:49320" returned an empty list of software certificates.
2024-09-26 11:29:18.042 – EasyUAClientOnLogEntry Message The OPC-UA server on endpoint URL "opc.tcp://127.0.0.1:49320" returned an empty server signature.
2024-09-26 11:29:18.044 – EasyUAClientOnLogEntry Message The client session on endpoint URL "opc.tcp://127.0.0.1:49320" has read server start time 09/04/2024 03:55:00 and build info ProductUri="urn:XXX.com:Kepware.KEPServerEX.V6:UA%20Server", ManufacturerName="Kepware", ProductName="KEPServerEX", SoftwareVersion="6.16", BuildNumber="217", BuildDate=08/01/2024 16:08:37.
2024-09-26 11:29:18.044 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6018 has successfully connected to endpoint URL "opc.tcp://127.0.0.1:49320". The server-assigned session Id is "ns=1;g=b9cd30ec-979a-4256-ab5f-e0669adc792b".
2024-09-26 11:29:18.045 – EasyUAClientOnLogEntry Message The OPC-UA subscription on client session with connect sequence number 6018 to endpoint URL "opc.tcp://127.0.0.1:49320" has been successfully created and checked, and given subscription ID 31843. Revised publishing interval is 250, keep-alive count is 20 and lifetime count is 1000.
2024-09-26 11:29:18.296 – EasyUAClientOnLogEntry Message Callback enqueuer overflow. The bounded queue capacity is 100000.
2024-09-26 11:29:18.395 – EasyUAClientOnLogEntry Message The overflow condition of the callback enqueuer is clearing. The overflow count was 28.
2024-09-26 11:29:26.046 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6018 is disconnecting from endpoint URL "opc.tcp://127.0.0.1:49320". Affect SDK engine: yes.
2024-09-26 11:29:26.544 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6018 has disconnected from endpoint URL "opc.tcp://127.0.0.1:49320".
2024-09-26 11:29:45.840 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6019 is connecting to endpoint URL "opc.tcp://127.0.0.1:49320".
2024-09-26 11:29:45.852 – EasyUAClientOnLogEntry Message The OPC-UA client session with connect sequence number 6019 for discovery URL "opc.tcp://127.0.0.1:49320" will use an endpoint selection policy that has warnings. The policy warnings are:
- OPCUA0021: An endpoint with obsolete security policy may be selected by this policy.

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