For our application we have a opcua server written with asyncua . The ignition server is subscribing to a heart beat tag which updated by the asyncua server every second.
On the opcua side, I found that there is one subscription missing acknowledgement. The wireshark shows that subscriptionID 128 is missing acknowledgement.
However if I change the tag’s subscription mode from subscribed to polled and back to subscribed. The asyncua server started to receive proper acknowledgement. Below is the output from asyncua.
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:32,215: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=859)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:32,215: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14647)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:33,220: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=860)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:33,221: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14648)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:34,226: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=861)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:34,227: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14649)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:35,232: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=862)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:35,233: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14650)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:36,239: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=863)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:36,240: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14651)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:37,243: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=864)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:37,244: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14652)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:38,250: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=128, SequenceNumber=865)]
[asyncua.server.subscription_service][INFO] 2022-01-18 17:22:38,252: publish request with acks [SubscriptionAcknowledgement(SubscriptionId=129, SequenceNumber=14653)]
Can I get some help on this issue. What could be the reason that ignition server has the tag updated but not sending acknowledgements.