By now we are familiar with the concept of DAG. Database availability group is nothing but a set of up to 16 Exchange Server 2016 mailbox servers that provide high availability or automatic database recovery database-level recovery from a database level. It is an improved clustering operation from Exchange Server 2010 onwards. I recommend you to read more about DAG if you are not familiar with, as this article gives only an insight to DAG creation and database copy configuration.
1. Open Exchange admin center (EAC), and navigate to Servers
2. Click on Database Availability Group on the right pane of the console
3. Click on + sign to add DAG
4. Enter the required information such as DAG Name, Witness Server, Witness directory IP address etc. and click on Save button
Note: If you plan to use a domain controller as witness server, please add it to the Exchange Trusted Subsystem security group. In addition, add the Exchange Trusted Subsystem into the Administrators group
This will create a Database Availability Group for you Exchange Server 2016 server.
1. Select the DAG name and click on Manage
2. Save once you add all required servers.
3. Now you can add database for High Availability.
Note: The process will take some time, as the failover cluster feature will be installed during the member addition process. Please wait patiently until the operation is finished.
1. Create Database on one of the DAG Members (follow the usual steps)
2. Select the Database for which you need High Availability, and click on Add database copy from more option.
[Note: You might require to re-login to EMC in case if you did not find the Add database copy option]
3. Follow the wizard and select the server to which you need to replicate the database to.
4. Save the changes, all the required folder and files will be created automatically similar to ver 2010 & 2013.
After the successful addition of database copy, you would be able to see that the database copy on server X1 status is Active Mounted and copy on X2 is Passive Healthy.
Creating the DAG and Adding members to DAG operations are much faster when you use Shell commands, however the through GUI it becomes easy to understand.
I will cover more operation on DBs and DAGs in future posts. Share your suggestions to improve the quality of information.
Recently when I was installing and configuring Exchange Server 2016 on a LAB infrastructure to test some configuration, I encountered the following error,
Could not load file or assembly 'Microsoft.Exchange.Net, Version=188.8.131.52, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The paging file is too small for this operation to complete. (Exception from HRESULT: 0x800705AF)
Initially I thought, it was due to the resources of the server, where as it turned out to be in complete installation of pre-requisites for Exchange Server 2016. I did not bother to follow any document, instead I did it my own thinking that all steps are complete.
I was able to fix the issue by following the instruction below,
Step 1: Add the server feature Microsoft Media Foundation, by running the below command.
Step 2: Install the .NET Framework 4.5.2 if you missed during the pre-requisite preparation.
.NET Framework 4.5.2:Download
If you have already installed .NET Framework 4.5.2, try to repair and restart the server. It would solve the issue and you will be able to launch EMS and EAC easily.