In this Tutorial we are going to use a new feature introduced in Exchange Server 2013 SP1 which is the capability to create a DAG object without an AAP (Cluster Administrative Access Point) which reduces complexity where a cluster name object (CNO) is no longer required when using his new configuration.
This Tutorial must be applied to new deployments, please do not change an existent DAG because that is not supported and it will create issues.
The DAG without an AAP reduces the complexity but has some points that must be validated by the Exchange Administrators before deciding to use it, as follows:
- The Active Directory requirement is reduced which means no more CNO (Cluster Name Object) to create a DAG
- There is no IP assignment
- There is no way to manage your cluster using the Cluster Failover Manager which means that PowerShell is your best friend in this scenario
- If you are using a disjoint namespace, then check this following Tutorial: http://ITPROCentral.com/error-creating-a-dag-without-aap-in-exchange-server-2013-sp1/
- Like any new feature, make sure that you test and validate well before moving to production in your environment
- You must check all your applications in use Today to make sure that they are compatible with a DAG without AAP, and that includes Backup software, AV and so forth.
Creating a new DAG without AAP…
Since we don’t have to worry about CNO objects, we can go straight to Exchange Admin Center (EAC) as administrator, click on servers and then database availability groups. Click on + (add) icon.
We need to define a new name for the DAG, the witness server and the witness directory, the difference here is that for the IP address we must use the IP 255.255.255.255 and that is the setting that defines a new DAG to be configured without AAP, after that click on save.
Just in case.. using Failover Cluster Manager…
Bear in mind that the Failover Cluster Manager is no longer valid to manage this new type of DAG, if you try to open you will receive an error message similar to the one below.
In this Tutorial we went over the steps to create a DAG without AAP using Exchange Admin Center and this procedure can be used on Exchange Server 2013 Service Pack 1 and later versions.