A database availability group (DAG) is a set of up to 16 Microsoft Exchange Server 2010, 2013, 2016, or 2019 Mailbox servers that provides automatic database-level recovery from a database, server, or network failure. Mailbox servers in a DAG monitor each other for failures. When you add a Mailbox server to a DAG, that Mailbox server works with the other servers in the DAG to provide automatic, database-level recovery from database, server, and network failures.
In Microsoft Exchange Server 2010, 2013, 2016, and 2019, DAG functionality replaces the following clustering functionality used with Microsoft Exchange Server 2007: cluster continuous replication (CCR), single copy cluster (SCC), and Local Continuous Replication (LCR). Exchange Server 2010, 2013, 2016, and 2019 do not use storage groups.
Add the computers that represent the individual computers of a DAG to the Master Management Group of an AppManager repository in Control Center. When you have added all DAG computers, create a server group, for example, EX2K_DAG_1, and add each DAG computer to that group.
For more information about adding computers to the Master Management Group of a repository and creating server groups, see the Control Center User Guide for AppManager.
Use the Discovery_ExchangeDAG Knowledge Script to discover configuration and resources for a Microsoft Exchange Server 2010, 2013, 2016, and 2019 Database Availability Group (DAG). Run Discovery_ExchangeDAG on an Exchange Server 2010, 2013, 2016, and 2019 server to discover the virtual object for DAG. After you discover the virtual object, you must run Discovery_Exchange2007 on the newly discovered object so you can discover the databases. For more information, see Section 2.6, Discovering Exchange Server Resources.
Before using the Discovery_ExchangeDAG Knowledge Script, set up the proper accounts and permissions. For more information, see Section 2.5, Permissions for Discovering Exchange Server Resources.
To discover resources in an Exchange Server 2010, 2013, 2016, and 2019 DAG, run the following Discovery Knowledge Scripts in the order listed:
|
Knowledge Script |
Resources Discovered |
|---|---|
|
Discovery_NT |
Run this script on each physical server that is a member of the DAG to discover Windows configuration and resources. |
|
Discovery_Exchange2007 |
Run this script on each physical server that is a member of the DAG to discover Exchange Server 2010, 2013, 2016, and 2019 databases. |
|
Discovery_ExchangeDAG |
Run this script on any one of the physical servers that is a member of the DAG to discover Exchange Server 2010, 2013, 2016, and 2019 DAG virtual objects. Running this script creates a new top-level object that represents the DAG in the TreeView of the Operator Center console. |
|
Discovery_Exchange2007 |
Run this script on the new top-level DAG node discovered in the previous step to discover the mailbox database resources in the DAG (which is the set of all mailbox databases managed by all servers in the DAG). |
Set the Values tab parameters as needed:
|
Parameter |
How to Set It |
|---|---|
|
General Settings |
|
|
Job failure event notification |
|
|
Event severity when job fails |
Set the severity level, from 1 to 40, to indicate the importance of an event in which the Discovery_ExchangeDAG job fails. The default is 5. |
|
Discovery |
|
|
Event Notification |
|
|
Raise event if DAG discovery succeeds? |
Select Yes to raise an event if DAG discovery succeeds. The default is No. |
|
Event severity when DAG discovery succeeds |
Set the severity level, from 1 to 40, to indicate the importance of an event in which DAG discovery succeeds. The default is 25. |
|
Raise event if DAG discovery fails? |
Select Yes to raise an event if discovery fails. The default is Yes. |
|
Event severity when DAG discovery fails |
Set the severity level, from 1 to 40, to indicate the importance of an event in which discovery fails. The default is 5. |
NOTE:If you previously ran the Discovery_Cluster Knowledge Script on nodes that now belong to a DAG, the Discovery_Cluster script discovered the Windows Cluster resource object, NT_CLU_MachineFolder. If you later run Discovery_ExchangeDAG on any node that belongs to the DAG, the script will not discover any new objects, because an object with same name was added using Discovery_Cluster KS. As a result, you will not be able to use Discovery_Exchange2007 KS to discover the databases on the DAG object, because Discovery_Exchange2007 does not work with the NT_CLU_MachineFolder resource object.
To address this situation, remove the Windows Cluster object that was discovered with the Discovery_Cluster Knowledge Script and use the Discovery_ExchangeDAG to discover the DAG object.
The following Mailbox server Knowledge Scripts can monitor DAGs in Exchange Server 2010, 2013, 2016, and 2019:
MBS_PublicFolderUsage (only for Exchange Server 2013, 2016, and 2019)