Log In
Home
07/09/2019
Offline
I have a question which popped up while cross reading the NodeManagement spec in part 4 and the general event Model in part 3. As far as I understand the event model is tied to a node, e.g. only a Node is able to emit an event (or notifications about data changes).
Is there also such a concept for the address space itself? The scenario I had in mind was a client creating new nodes or references which a server might have to care about and hence having "meta events" about such address space changes might be a thing in OPC UA. Regarding the specs I cannot see such a concept since everything is node based, but I really want to clear this question up since this is quite important regarding implementation architectures.
05/30/2017
Offline
The "Server" node is a special Event Notifier that reports all events no matter what Notifier they are associated with.
Any global event events are reported by the Server node too (i.e. i.e. the SourceNode = Server).
02/24/2014
Offline
Look at 6.5.7 Auditing for NodeManagement Service Set in Part 4 (version 1.04) of the spec. In servers that support it, each change you are concerned about generates an event of AuditNodeManagementEventType or a subtype.
07/09/2019
Offline
Hey again, thanks for the quick response!
My question was not so much about how events are routed, even though I didn't know about the special role of the server node here. I was talking more about if there are special "meta events" about address space changes like the creation of a new node, done e.g. via the node management service set. What do you mean by global events?
05/30/2017
Offline
Global events are any event that is not associated with a single node. i.e. global events include your meta events.
07/09/2019
Offline
zbynekz said
Look at 6.5.7 Auditing for NodeManagement Service Set in Part 4 (version 1.04) of the spec. In servers that support it, each change you are concerned about generates an event of AuditNodeManagementEventType or a subtype.
OK, thanks for the hint! So this is an example of global events which you can trace. But ... those events are just for auditing (in the end you just want to read those events). Are there also global events which trigger further logic on e.g. other services?
Randy Armstrong said
Global events are any event that is not associated with a single node. i.e. global events include your meta events.
Are you refering to the audit events?
1 Guest(s)
Usage Policy