This is the continuation from the Configuring the DAG Replication and Failover in Exchange Server 2010 Part-2. In this part I will show you how to create mailbox database copy, how to test the DAG failover availability.

Creating the Mailbox Database Copy:-

To create the Mailbox Database Copy open the exchange management console, then select the Mailbox under the organization configuration from the console tree, from the right panel select the Database Management tab then right-click the appropriate database and select the add Mailbox Database Copy

Figure: 1

For selecting the mailbox server who is going to host the database copy click the browse button

Figure: 2

In this example I have only one mailbox server so I am selecting mbx01 to host the copy or the mbx01 database. If you have multiple mailbox servers you can choose multiple mailbox servers. Click ok to add the mailbox server.

Note: maximum number of mailbox server which can host the single database copy is 16

Then click next button to create the Mailbox Database Copy

Figure: 3

Our Mailbox Database Copy has been successfully created, we can see the confirmation from the below screenshot. Click finish to exit the configuration task

Figure: 4

In the below screenshot we can see mailbox database DAG_DB has two copies of the database and it is hosted in MBX01 and MBX02. DB01 is located on MBX01 and it doesn’t have replication copy.

Figure: 5

We are created the Database copy for testing the DAG functionality. Now we need to create a mailbox in DAG_DB database.

For that right-click the Mailbox under the Recipient Configuration from the console tree then select the New Mailbox.

Figure: 6

Select the User Mailbox and click Next->>

Figure: 7

Select the New User and click Next->>

Figure: 8

Fill the user account information details and password, Click Next to continue

Figure: 9

Select the DAG_DB (Copy enabled mailbox) and click ok

Figure: 10

Click next continue, in the next the step it will prompt you for the creating the archive mailbox, if you want to creating the archive mailbox you can select the check box. In this scenario I am not using the archive feature.

After the archiving prompt click next then it will ask you for the confirmation for creating the mailbox, If all the information’s are correct click New to create the Mailbox

Figure: 11

Now we are created the Mailbox

Figure: 12

The below screenshot we can see the mailbox name shareef is created in DAG_DB (copy enabled database). You can see that the administrator Mailbox is located in DB01. We are not enabled the database copy on DB01.

Figure: 13

Now it’s the time for test the DAG failover functionality, so I am login to OWA with the username shareef

Figure: 14

This is the first time I am login with the username shareef, so need to choose the language and time zone. Right now I am in Qatar so I am choosing time zone as +3.00 Kuwait, Riyadh and I am comfortable with the English language.

Click OK to login to the OWA Mailbox

Figure: 15

Right now I don’t have any mail in my inbox so I am composing a mail and sending to user shareef and administrator subject as DAG Replication Test.

Figure: 16

Figure: 17

You can see from the below screenshot that the user shareef is received the mail subjected as DAG Replication Test

Figure: 18

Now I am shutting down the MBX01 mailbox server, MBX01 is holding the DB01 database.

The below mentioned screenshot you can see that the DAG database DAG_DB copy status on MBX01 is showing ServiceDown

Figure: 19

The DB01 database copy status is also showing ServiceDown

Figure: 20

This is the screenshot of the DAG network, in that the MBX01 server network interface IP address (192.168.1.161) is showing unavailable.

Also the status of the MBX01 node in Failover Cluster is showing Down

Figure: 21

Figure: 22

This is the status of the network adapter in Cluster network and it is showing Unavailable.

Figure: 23

Now we are confirmed that the Mailbox Server MBX01 is completely down, that means the database DB01 is also down. In this situation I can’t login to the administrator mailbox, it has to give an error when I try to login to the administrator mailbox.

I am going to login to OWA with the username administrator

Figure: 24

As I am login first time with the administrator user ID, I have to choose the Language and Time zone.

Click OK to login to the administrator mailbox

Figure: 25

This is the error we will get when the mailbox database is down or the server itself down. The error shows that the administrator mailbox is unavailable that means the database where the administrator mailbox is down.

We confirm that the administrator mailbox is not working we need to find out the whether the mailbox for user shareef is available or not.

Figure: 26

This is the mailboxes of both shareef and administrator. In this we can see the mailbox for shareef is available and accessible without any issue.

Through this we identified that DAG failover is working perfectly.

Figure: 27

Related posts:

1. Configuring the DAG Replication and Failover in Exchange Server 2010 Part-2
2. Configuring the DAG Replication and Failover in Exchange Server 2010 Part-1