AX 2012 adds a new end point to every AOS instance to provide System and Custom WCF Services. This is an addition to the Remote Procedure Call (RPC) end point we have had since AX 4.0. RPC is covered by the AX internal Load Balancing functionality (Connection Oriented scheme). To provide redundancy at the WCF level, Windows Network Load Balancing (WNLB) or similar technology (appliances etc.), is required to be able to address a set of AOS instances as a common resource (virtual IP/cluster name).
Question 1
- Does the AX Windows Client (and other AX components like Reporting Extentions, Enterprise Portal etc.) secure that the RPC connection and the WCF end point is provided from the same AOS instanceOR could the connection end up having the RPC connection at one AOS instance and the WCF end point on another AOS instance?
For AOS instances only handling integration load utilizing WCF Services (no interactive user load), I can see the logic of using WNLB...I can also see the logic if the AX Windows Client and Business Connector in fact can have the RPC connection against one AOS instance and the WCF end point against another AOS instance, but...
Question 2:
- What happens if a user is connected to one AOS instance (both RPC and WCF) and the WCF end point fails? I guess the user has to log off and on again to reestablish a valid end point for the WCF communication (Metadata, Session and Query Service), but this is only a guess.
I don't have the luxory of running a lab for this "real life" scenario and I hope someone can help me understand this a little bit better.
Reference:
Configuring network load balancing for services [AX 2012]