Dynamics AX: Tuning an AOS for best performance
Optimizing an AOS depends on what the AOS is used for. For
example, an AOS that is load balanced should only allocate a certain number of
resources on the server it is running on. Similarly, an AOS that is only used
for the Enterprise Portal may not want to allow access to rich client users.
Therefore, before taking any steps to optimize the performance of an AOS, make
sure you have properly defined a role that the AOS has.
There are two ways to distribute load in a Dynamics AX environment. They are
the following:
• Non-load-balanced cluster
• Load-balanced cluster
A cluster of AOSes are simply a group of AOSes. It doesn't necessarily mean
that they are load balanced. However, a load-balanced cluster does indeed mean
that a group of AOSes in a cluster are load balanced. The following sections
will describe in more detail what a non-load-balanced cluster and a
load-balanced cluster are.
Non-load-balanced cluster
A non-load-balanced
cluster does not have a main AOS that is dedicated to
delegating client connections to the appropriate AOS. Instead, each AOS in the
cluster acts independently. Each AOS has to be provided in the client
configuration file for the client to connect. Based on a list of provided AOS
servers in the client configuration file, the client will attempt to access
each server in the order listed to find an available server. If a server's
workload has reached its maximum level, then the client will simply attempt to
connect to the next AOS.
Load-balanced cluster
Microsoft Dynamics AX
provides the option to load balance two or more AOS's together. This is similar
to how a web farm works for a SharePoint site. Alternatively, you may opt to
use hardware or another software solution to load balance AOS access. It is
recommended to have one AOS for no more than 50-60 users. In a load balanced
cluster, one AOS is a dedicated load balancer, delegating client connections to
the appropriate AOS. It is not directly used either for interactive purposes or
for processing application code. Once a client is connected to the load
balancer AOS, it will then determine which AOS it should connect to. If an AOS
goes down, the load balancer AOS will automatically re-route clients to an
active and available AOS without having to make any modifications to client
configurations. Also, as a company grows and more users are needed, it is as
simple as installing a new AOS and connecting it to the load balancer.
As previously mentioned, to set up load balancing, we must set
up one AOS as the load balancer. Afterwards, each additional AOS in the
load-balanced cluster will automatically listen for client connection requests
from the Load Balancer AOS.
However, in order for an AOS to be a load balancer, it must first satisfy the
following criteria:
• Cannot be a Batch Server.
• Must be an AOS that is active.
The following steps describe the process of setting up load balancing in
Microsoft Dynamics AX 2009:
1. Open the Cluster configuration form by going to Administration | Setup |
Cluster configuration.
2. Once in the Cluster configuration form, click on the Map AOS
instances to
clusters tab.
3. In the Map AOS instances to clusters tab, select the AOS
instance in which
to act as the load balancer and mark the Load Balancer field.
As you can see, setting up a load-balanced cluster in Dynamics
AX is quite simple and requires very little configuration or tweaking of
settings. When load tends to increase and performance degrades, adding a new
AOS into a load-balanced cluster greatly improves performance and is quite
simple to do. You can add as many AOS's as desired to a cluster. The process is
the same for every additional AOS that is added.
To summarize, a non-load-balanced cluster requires more administrative work to
update the client configuration files with the available AOS's. However, with a
load-balanced cluster, the AOS that acts as the load balancer, once setup with
all the available AOS's will automatically delegate clients to an AOS in a
cluster with the most available resources.
Certainly, having a load-balanced cluster may seem like a desired setup to go
with, as it requires less administrative maintenance. It also provides a method
for consolidating specific business functions. For example, one cluster of
AOS's may be specifically dedicated to batch processing. Similarly, another
cluster may be dedicated to an external Enterprise Portal site that can
experience a significant load of external user access while a cluster for
internal users may not experience as much load. Also consider that in a
load-balanced cluster, at least three AOSes are required while in a similar
non-load-balanced cluster, only two are required—to provide load distribution.
