How to Set Up Exchange 2019 Database Availability Groups


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Database Availability Groups (DBAs) are groups of database instances that provide high availability for the application. DBA’s rely on a system called failover clustering, which is set up to monitor and automatically detect problems within the cluster before they can cause downtime. The goal of an Exchange 2019 Database Availability Group is to minimize data loss from unplanned outages in your business needs.

The “exchange 2019 dag setup step by step” is a guide that can help you set up Exchange 2019 Database Availability Groups. It will also show you how to configure your DAGs.

How to Set Up Exchange 2019 Database Availability Groups

At least one Exchange database availability group exists in a highly available Microsoft Exchange setup. Availability Groups for Databases are essential for keeping a collection of Mailbox servers extremely available and scalable.

In this article, you’ll learn how to use the web interface and PowerShell to establish and configure Availability Groups for Databases in Exchange 2019. You’ll also learn how to connect a database to the group and add member servers.

Overview of Availability Groups for DatabasesOverview of Availability Groups for Databases


This is a hands-on course that will need an established environment to follow along with. To make sure your setup follows the guide, make sure you have:

  • Exchange Server 2019 is installed on two servers.
  • Microsoft Exchange is installed on all Exchange servers in the same version. It is not possible to mix versions. Ex01 and Ex02, two servers running Windows Server 2019 Standard Edition and Exchange Server 2019, will be used in this tutorial.
  • As the Witness Server, you’ll need a Windows Server 2016+. This guide will show you how to set up a witness server named FS01.

You won’t require a witness server if you have an odd number of Exchange nodes. Node majority will be used in the cluster.

Setting up the Witness Server

A witness server is required before you can construct a database availability group with an even number of nodes. All members of the Exchange Trusted Subsystem AD Universal group have access to a folder on the witness server. The witness server is used to ensure quorum and secure a voting majority.

In Microsoft’s documentation, you can learn more about witness servers and how they function inside availability groups.

While on the FS01 server, you should:

To begin, join the local Administrators group to the Exchange Trusted Subsystem AD group. The Exchange Trusted Subsystem AD group has full access to all Exchange-related items and is a high-privilege AD group.

1647495225_126_How-to-Set-Up-Exchange-2019-Database-Availability-GroupsTo the Local Administrators group, add the Exchange Trusted SubSystem.

Then, create a new folder called C:DAGWitness or something similar.

That concludes the witness server configuration.

Using Exchange Admin Center to create a Database Availability Group

Now let’s get down to business and create an Exchange database availability group!

  1. Go to https:///EX01/ecp to access the Exchange Admin Center on EX01. One of the mailbox servers used in the lesson is EX01.

2. Once in the Exchange Admin Center, click on servers —> Availability Groups for Databases as shown below.

Availability Groups for DatabasesAvailability Groups for Databases

3. When you click the Plus symbol, the following dialog appears. Make sure you complete out all of the mandatory fields shown below.

  • Name of the database availability group — This is the group’s name. It will be the name under which the DAG will be managed and communicated with.

The group name is limited to 15 characters.

  • The name of the server that is hosting the witness folder. The server used in this lesson is FS01.
  • Witness directory – The absolute path to the newly established directory.

For the Witness directory, always use the local path rather than a UNC path.

  • IP addresses for database availability groups – The IP address that will be allocated to the DAG.

Parameters needed by DAGParameters needed by DAG

4. To create the group, click Save after you’ve completed all of the essential data.

If you have any issues at this point, be sure to check out the Troubleshooting section below.

Adding a Database Availability Group Member Server

The database availability group has been built, but it won’t accomplish anything unless some nodes (member servers) are added to it. While remaining in the Exchange Admin Center, perform the following:

  1. Click the Manage DAG membership icon next to the newly established group, as seen below.

Adding new DAG membersAdding new DAG members

2. Next, add the required member servers. Add EX01 and EX02 to this tutorial and click Save.

Once the member servers have been added, a wizard will install and configure the Windows Failover Cluster on the nodes.

Adding new DAG members progressAdding new DAG members progress

It may take some time to build the cluster, so relax and get a cup of coffee.

If everything went well, you should now see the group’s member servers listed below.

As members, servers are added to the DAG.As members, servers are added to the DAG.

The database availability group has been activated. You may add mailbox databases to the group at this point.

Creating a Database for Mailboxes

It’s time to add a mailbox database once you’ve built the group and added the member servers. While remaining in Exchange Admin Center, do the following:

  1. Navigate to servers —> databases.

2. Select the database you want to link to the DAG and then click Add database copy. The EX01-DB and EX02-DB mailbox databases are used in this lesson. A window will appear, prompting you to pick the mailbox server that will host an extra copy of the specified mailbox database.

DAG Database AdditionDAG Database Addition

3. Click on Browse and select the desired server from the list and click on OK —> Save

Choosing an extra server to house a replica of the mailbox database Choosing an extra server to house a replica of the mailbox database

The seeding procedure will be started, and the database will be copied to the chosen destination server.

Seeding is the process of adding a mailbox to a group for the first time. The process of seeding involves moving a database from one server to another. Seeding is a server resource-intensive procedure, therefore schedule it for non-busy days.

1647495233_670_How-to-Set-Up-Exchange-2019-Database-Availability-GroupsThe seeding procedure

4. Click the databases tab to validate that this database is now hosted on EX01 and EX02. Notice how the database has been moved to SERVERS WITH COPIES.

The ACTIVE ON SERVER will also be shown. The database EX01-DB is presently enabled and mounted on the EX01 server for this lesson.

EX01-DB is now available on both EX01 and EX02 servers.EX01-DB is now available on both EX01 and EX02 servers.

It is advised that the volume be formatted using GPT rather than MBR since it can expand beyond Two TB, however if you are trapped with this constraint and wish to convert to GPT without losing data, third-party solutions may help. has further information about GPTGen.

Using PowerShell to create a Database Availability Group

You may do all of the aforementioned steps to build and configure a database availability group using PowerShell as an alternate technique (and to save time)! Let’s look at how.

When connected to any Exchange Server:

  1. Run the following command in the Exchange Management Shell. A database availability group is created using this command:
  • With the acronym DAG.
  • Using the FS01 witness server.
  • On the witness server, use a pre-created folder named C:DAGWitness.
  • Assigning an IP address to the DAG

-DatabaseAvailabilityGroupIPAddresses ‘’ -Name DAG -WitnessServer FS01 -WitnessDirectory C:DAGWitness

You should see the following output after everything is finished.

Using Powershell to create a DAG Using Powershell to create a DAG

If you have any issues at this point, be sure to check out the Troubleshooting section below.

2. Add the member servers to the database availability group using the Add-DatabaseAvailabilityGroupServer cmdlet. Use Get-ExchangeServer to discover all Exchange servers and add them all to the database availability group called DAG, as shown below.

Add-DatabaseAvailabilityGroupServer -Identity DAG | Get-ExchangeServer

Alternatively, you might use the MailboxServer argument to add each member server one at a time, as illustrated below.

-Identity DAG –MailboxServer EX01 –Add-DatabaseAvailabilityGroupServer

Using the Get-DatabaseAvailabilityGroup cmdlet, check that the member servers have been added. If everything is in order, all member servers should appear in the Member Servers column, as seen below.

The DAG's membersThe DAG’s members

4. Use the Add-MailboxDatabaseCopy cmdlet to add the mailbox database to the database availability group. The command below copies the EX01-DB database from EX01 to EX02, allowing EX02 to have a second copy of the database.

-Identity EX01-DB -MailboxServer EX02 Add-MailboxDatabaseCopy

5. On the destination server, restart the Microsoft Exchange Information Store ****service.

Finally, run Get-MailboxDatabaseCopyStatus to verify that the mailbox was successfully added. If everything works well, you should get something like this.

The database has been updated. The database has been updated.

One database is Mounted, whilst the other is Healthy. The Mounted database is the copy that users see, while the Healthy database is the backup copy. If the Mounted copy fails, Exchange may switch to the backup copy.


You may encounter a variety of issues when configuring the database availability group. If that’s the case, try the troubleshooting procedures below.

Always look at the Windows Event log first since it has more information about the main reason and why things aren’t functioning properly.

IPv6 is turned on…

One of the most typical error messages you’ll see is Windows Failover Clustering isn’t installed on…

A database availability group administration procedure on the server failed. Error The procedure was unsuccessful. Incorrectly set static addresses might cause CreateCluster failures. Windows Failover Error ‘EX01’ does not have clustering installed.

Disable IPv6 by creating a new 32-bit DWORD registry value named DisabledComponents under HKEY LOCAL MACHINESYSTEMCurrentControlSetServicesTcpip6Parameters with the value fffffffffffffffffffffffffffffffffffffffffffff Restart the server after everything is done.

With 0x5, CreateCluster() fails. Access is denied error

You can run into another typical issue caused by a permissions issue.

A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: An error occurred while attempting a cluster operation. Error: Cluster API failed: “With 0x5, CreateCluster() fails. Access is denied error”. [Server:EX01.test.local]

To resolve this issue, deactivate the database availability group AD computer object and provide Full Control of the AD object to the Exchange Trusted Subsystem AD group, as indicated below.

1647495238_614_How-to-Set-Up-Exchange-2019-Database-Availability-GroupsAdding the Trusted SubSystem group to Exchange

Steps to Follow

Look at how to use Acquire-MailboxDatabase and Other Cmdlets to get Mailbox Database and execute actions like Move, Mount, and Repair.

Also, under How to Import a PST into Outlook, there are numerous methods to import PST to Outlook.

The “add dag member exchange 2016” is a step-by-step guide that will help you set up Exchange 2019 Database Availability Groups.

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