Configure database availability group properties
Summary: You can use the EAC or the Exchange Management Shell to configure the properties of a database availability group (DAG), including DAG IP address configuration, the witness server, and the witness directory.
The Shell enables you to configure DAG properties that aren't available in the EAC, such as alternate witness server and alternate witness directory information, the TCP port used for replication, and datacenter activation coordination (DAC) mode.
What do you need to know before you begin?
Estimated time to complete: 1 minute
You need to be assigned permissions before you can perform this procedure or procedures. To see what permissions you need, see the "Database availability groups" entry in the High availability and site resilience permissions topic.
DAG property values are stored in both Active Directory and the cluster database. However, some properties are stored only in the cluster database. As a result, the underlying cluster for the DAG must be running and have quorum to set the properties for:
For information about keyboard shortcuts that may apply to the procedures in this topic, see Keyboard shortcuts in the Exchange admin center.
Use the EAC to configure database availability group properties
In the EAC, go to Servers > Database Availability Groups.
Select the DAG you want to configure and click .
Use the General page to view DAG membership and operational status, and to configure the DAG's witness server, witness directory, and automatic network configuration:
Witness server: The host name or fully qualified domain name (FQDN) of the witness server for the DAG. Although this is a required property for all DAGs, the witness server is used when there is an even number of DAG members and the quorum model in use by the cluster is Node and File Share Majority.
Witness directory: The full path of the directory used to store the witness.log file on the witness server. Although this is a required property for all DAGs, the witness directory is used only when the DAG's witness server is in use.
Database availability group members: A read-only field that displays a list of DAG members and their current operational status.
Configure database availability group networks manually: A check box that you select when you want to configure all DAG networks manually. When the check box is clear, the system configures DAG networks automatically based on network interface configuration, and the Set-DatabaseAvailabilityGroupNetwork and New-DatabaseAvailabilityGroupNetwork cmdlets are disabled for the DAG.
Use the IP addresses page to view and modify the IP addresses assigned to the DAG:
Select an existing IP address and click to modify it.
Select an existing IP address and click the minus icon (delete) to remove it.
Enter an IP address and click to add it to the DAG.
Click Save to save any changes that were made.
Use the Exchange Management Shell to configure database availability group properties
This example sets the witness directory to C:\DAG1DIR for the DAG DAG1.
Set-DatabaseAvailabilityGroup -Identity DAG1 -WitnessDirectory C:\DAG1DIR
This example preconfigures an alternate witness server of MBX3 and an alternate witness directory of C:\DAGFileShareWitnesses\DAG1.contoso.com for the DAG DAG1.
Set-DatabaseAvailabilityGroup -Identity DAG1 -AlternateWitnessDirectory C:\DAGFileShareWitnesses\DAG1.contoso.com -AlternateWitnessServer MBX3
This example configures the DAG DAG1 to use Dynamic Host Configuration Protocol (DHCP) to obtain an IP address.
Set-DatabaseAvailabilityGroup -Identity DAG1 -DatabaseAvailabilityGroupIPAddresses 0.0.0.0
This example configures the DAG DAG1 to use a static IP address of 10.0.0.8.
Set-DatabaseAvailabilityGroup -Identity DAG1 -DatabaseAvailabilityGroupIPAddresses 10.0.0.8
This example configures the multi-subnet DAG DAG1 with multiple static IP addresses.
Set-DatabaseAvailabilityGroup -Identity DAG1 -DatabaseAvailabilityGroupIPAddresses 10.0.0.8,10.0.1.8
This example configures the DAG DAG1 for DAC mode.
Set-DatabaseAvailabilityGroup -Identity DAG1 -DatacenterActivationMode DagOnly
This example configures the replication port for the DAG DAG1 to be 63132.
Set-DatabaseAvailabilityGroup -Identity DAG1 -ReplicationPort 63132
After changing the default replication port for a DAG, you must manually modify the Windows Firewall exceptions on each member of the DAG to allow communication to occur over the specified port.
How do you know this worked?
To verify that you've successfully configured the DAG, do the following:
In the Exchange Management Shell, run the following command to display DAG configuration settings and verify the DAG was configured successfully.
Get-DatabaseAvailabilityGroup <DAGName> | Format-List