Applies to: Exchange Server 2010

Topic Last Modified: 2011-03-19

Use the Add-DatabaseAvailabilityGroupServer cmdlet to add a Mailbox server to a database availability group (DAG). A DAG is a set of Mailbox servers that provide automatic database-level recovery from a database, server, or network failure. When a Mailbox server with replicated databases is added to a DAG, it works with the other servers in the DAG to provide automatic, database-level recovery from database, server, and network failures.

To add a Mailbox server to a DAG, the Mailbox server:

  • Must be running Windows Server 2008 Enterprise Edition or Windows Server 2008 R2 Enterprise Edition;
  • Must not belong to any other DAGs;
  • Must be in the same Active Directory domain as all other Mailbox servers in the DAG; and
  • Must not be configured as an Active Directory directory server.

Add-DatabaseAvailabilityGroupServer -Identity <DatabaseAvailabilityGroupIdParameter> -MailboxServer <ServerIdParameter> [-Confirm [<SwitchParameter>]] [-DomainController <Fqdn>] [-WhatIf [<SwitchParameter>]]

Parameter Required Type Description




The Identity parameter specifies the name of the DAG to which the server is being added.




The MailboxServer parameter specifies the name of the Mailbox server being added to the DAG.




The Confirm switch causes the command to pause processing and requires you to acknowledge what the command will do before processing continues. You don't have to specify a value with the Confirm switch.




The DomainController parameter specifies the fully qualified domain name (FQDN) of the domain controller that writes this configuration change to Active Directory.




The WhatIf switch instructs the command to simulate the actions that it would take on the object. By using the WhatIf switch, you can view what changes would occur without having to apply any of those changes. You don't have to specify a value with the WhatIf switch.

A computer object for a DAG is created in Active Directory when the first server is added to the DAG. This object is used to authenticate servers to each other within a DAG.

To add the first server to a DAG and create a computer object for the DAG, the Exchange Windows Permissions security group must have the appropriate rights to add computer accounts to the domain. Alternatively, a computer account can be created and disabled prior to adding the server. Adding the first server to the DAG enables the computer account for the DAG. Thus, the account used for the task doesn't need permissions to add a computer account to the domain. If you are pre-creating the computer account, the name of the account must match the name for the DAG. For example, if the DAG is named DAG1, the computer account must be named DAG1.

You need to be assigned permissions before you can run this cmdlet. Although all parameters for this cmdlet are listed in this topic, you may not have access to some parameters if they're not included in the permissions assigned to you. To see what permissions you need, see the"database availability group" entry in the High Availability Permissions topic.

Error Description

Exchange server %ServerName% was not found. Please make sure you have typed it correctly.

The task couldn't find a Mailbox server with the specified name.

The operation could not be performed because %SpecifiedName% could not be found.

The task couldn't find a DAG with the specified name.

This example adds a Mailbox server named MBX1 to a DAG named DAG1.

Add-DatabaseAvailbilityGroupServer -Identity DAG1 -MailboxServer MBX1