How to Setup a Dedicated Backup Network in Exchange 2010 DAG

Every IT organization needs to perform backups to ensure data integrity and recovery in the event of data loss caused by a system failure, accidental deletion by a user, or corruption.

One item that is regularly overlooked when architecting and implementing a backup solution is the use of a dedicated backup network that's separate from the production network. Each server to be backed up should have two network cards. The first network card should be used to connect to the production network. The second network card should be used to connect to the backup network.

Example : This Example details the process of setting up Backup network in Exchange 2010 DAG scenario.

 
In the above Scenario we have DAG implemented, thus we should have three NIC.
1 – Mapi Network    -  That will be used to connect to production network
2 – Replication netowrk  – That would be used for log shipping
3 – Backup network   – That would be used for backup

Recommendation :

While setting up dedicated Backup network, another NIC needs to be added to each of the mailbox servers and  connected to another network such as 10.200.20.1/24 with a corresponding subnet mask 255.255.255.0. 

Uncheck "Register this connection address in DNS" for backup network 

Add backup network address in the host file . On MBX server add the Backup server address in the host file and On the Backup server add mailbox servers backup Nic address in the host file.

We recommend that you verify whether the Backup server is able to ping the Exchange Server's backup network address (10.200.20.2/3). Similarly, the Exchange Sever should be able to ping the Backup server’s backup network address (10.200.20.1).      

 Backup server should resolve the Fqdn of both the mailbox server name and vice versa.

 Once we met all of the above recommendation, Lets go ahead and run the following command in Exchange Management Shell.

 New-DatabaseAvailabilityGroupNetwork -DatabaseAvailabilityGroup DAG1 -Name DagNet3 -Description "Backup network" -Subnets 10.200.20.0/24 -ReplicationEnabled:$False -ignorenetwork:$ True     

Note : It has been observed and found in some cases,  as soon as you remove a subnet from a DAG network, it will be automatically rediscovered, and added to a brand-new DAG network. So After the network has been disabled and ignored, please go to failover cluster management, set the network to be disabled for cluster use Because they are disabled at the cluster level, they will not be re-discovered and re-added.

People who are using DPM 2010 Please follow below link to achieve the same.

Using Backup Network Address
http://technet.microsoft.com/en-us/library/ff399746.aspx

Please email at mail@messagingserversupport.com for any queries or feedback.
 
Cheers,
Team MSS 

Exchange Server 2010