How to: Resolve Conflicts After Importing a Model [AX 2012]

When you import a model into the model store, the resources in the model may have conflicts with resources in other models that are already part of that layer. If you use the push option when importing the model, the conflicting resources will be put into a new conflict model that is located in the patch layer for the current layer in the AOS. This new model will have a name that indicates it contains resources that have caused a conflict. For example the model named Facility Management (Conflict 1) contains the resources that caused a conflict when the Facility Management model was being imported.

Often, it is a developer responsibility to help resolve conflicts that occur when a model is imported. Use the following procedure as a general guideline to help you through this process.

Resolving Conflicts after Importing a Model

To resolve conflicts after importing a model

1. Determine whether any conflicts occurred during the model import process.

   • If you imported a model from the command line, the results returned from the command will indicate whether conflicts occurred during the import process.

   • If you do not know the results of the import process, use the Models installed command as described in How to: View Model Information to view the list of models that are installed. If you see any conflict models in a patch layer, they will contain the resources that caused the conflict.

2. Retrieve the list of resources that caused conflicts. Use the view command to see the list of resources in the conflict model. These are the conflicts that you have to resolve. For detailed information about how to list resources in a model, see How to: View and Verify Contents of a Model. For example, the following command uses axutil.exe to list resources in the Facility Management (Conflict 1) model:

   axutil.exe view /model:"Facility Management (Conflict 1)" /verbose

3. In the AOT, select a resource that has a conflict. Right-click the resource and choose Compare. In the Comparison window, click Compare to see the differences between the resource in the patch layer and the resource in the main layer.

4. Resolve the conflict. There are many ways to resolve the conflict, depending on the resource type and the actual conflict. Some of the ways to resolve the conflict include the following:

   • Use the information and the available actions from the Comparison window to merge changes from the conflict model into an existing layer.

   • Make a change in the resource in an existing model in the current layer. For example, if two different models in the layer have modified the same resource, you could consider creating a new “shared” model in the layer that contains a single version of the resource that can be used by both of the other models.

   • Switch to the patch layer and modify the resource there. In some cases, this is the easiest way to resolve the conflict.

     Tip

     You can switch to the patch layer by creating a new configuration with the Microsoft Dynamics AX 2012 Configuration tool. You can also switch to a specific patch layer by using the following command to start Microsoft Dynamics AX:

     Ax32.exe –AOL=USP

5. Repeat the conflict resolution process for each resource in the conflict model.

After you have resolved all of the conflicts, consider removing the conflict model from the patch layer. That way, somebody looking at the system will not assume that there are model conflicts that have to been resolved. If you are leaving a resource in the patch layer, move the resource out of the conflict model into another model in the patch layer. Then delete the conflict model.

AOS clusters without a dedicated load balancer [AX 2012]

You can configure Microsoft Dynamics AX Application Object Server (AOS) clusters that include a dedicated load balancer. You can also configure clusters that do not include a dedicated load balancer. This topic describes planning considerations for an AOS cluster that does not include a dedicated load balancer.

Overview

The following figure shows how a client establishes a connection with an AOS instance in a cluster when a dedicated load balancer is not present.

1. When a Microsoft Dynamics AX client starts, the client reads the list of AOS instances that is specified in the Microsoft Dynamics AX 2012 Configuration utility. The client initiates a handshake with the first AOS instance in the list. If the first AOS instance does not respond, the client initiates a handshake with the next AOS instance in the list. The client continues in this manner until the handshake occurs.

2. The AOS instance that received the client request queries the database and all active AOS instances in the cluster. The AOS instance returns to the client a list of all active AOS instances in the cluster, sorted by workload. The server that has the smallest workload is at the top of the list. The workload is based on the number of connected clients, divided by the maximum number of clients that are allowed on the server.

3. The client attempts to connect to each AOS instance in the sorted list until a successful connection is established. The client then uses the AOS instance that it connected to for the whole session.

Considerations for using an AOS instance in a cluster that does not include a dedicated load balancer

• If a dedicated load balancer is not present, each AOS instance in the cluster functions as both an active AOS instance and a load balancer.

• An active AOS instance has higher hardware requirements than an AOS instance that functions as a dedicated load balancer.

For information about how to configure load balancing clusters, see Create a load balancing cluster post.

Create a load balancing cluster [AX 2012]

You can distribute the user load in Microsoft Dynamics AX across multiple instances of Application Object Server (AOS) by creating a load balancing cluster.

Clustering overview

Microsoft Dynamics AX offers two types of load balancing clusters:

• A cluster that includes a load balancer

• A cluster that does not include a load balancer

A cluster that includes a load balancer

If you set up a cluster that includes a load balancer, the load balancing AOS instance is dedicated to distributing the user load. The load balancing AOS instance does not process Microsoft Dynamics AX business logic or data.

In this configuration, you must set up client configurations to connect to the load balancing AOS instance. You can then add and remove other AOS instances from the cluster without updating client configurations.

When a client starts, it connects to the load balancing AOS instance. The load balancing AOS instance returns a list of active AOS instances in the cluster, sorted by workload. The client attempts to connect to the first AOS instance in the list. If that connection fails, the client attempts to connect to the second AOS instance in the list, and so on.

A cluster that does not include a load balancer

If you set up a cluster that does not include a load balancer, each AOS instance functions as both a load balancer and an active AOS instance that accepts client connections.

When a client starts, it sends a request to the first server that is listed in the client configuration. That server returns the list of active AOS instances in the cluster, sorted by workload. The client attempts to connect to the first AOS instance in the list. If that connection fails, the client attempts to connect to the second AOS instance in the list, and so on.

Before you begin

Before you can create a cluster, you must install multiple AOS instances. Each instance must point to the same database. For more information, see Install multiple AOS instances and Configure an AOS to access a different database.

Create a cluster

1. Click System administration > Setup > System > Cluster configuration.

2. Press CTRL+N to create a new cluster.

   Caution

   You cannot configure the Non Load Balanced AOS Instances as a load balancing cluster. The Non Load Balanced AOS Instances is a default entity that enables AOS communications for non-load balanced AOSs. To create an AOS cluster, you must create a new cluster.

3. Enter a name and description for the cluster.

4. Press CTRL+S to save your changes.

Add an AOS instance to a cluster

1. Click System administration > Setup > System > Cluster configuration.

2. In the Map AOS instances to clusters section, select an AOS instance.

3. If you want the AOS instance that you selected to function as a load balancer, select the Load balancer option.

   Note

   If an AOS instance is used as a load balancer, it cannot be used as a batch server.

4. Click the Cluster name field to display a list of available clusters. Select the cluster that you want to add the AOS instance to.

5. Press CTRL+S to save your changes.

Change client configurations

If the cluster uses one or more load-balancing AOS instances, set client configurations to connect to these load balancing AOS instances.

Use the Microsoft Dynamics AX Configuration utility to change client configurations. For more information, see my post Manage a client configuration .