Exchange 2010 /2013 DAG Design

Hi All,

I Have Gone through some Articles and Blogs where i read about the DAG Design and Member server placement in Site Resiliency Scenarios..

I just want to know what and how many DAG Designs we can propose to Customers.

As per my knowledge and study i came across -

(A) Active/Passive Model with Shared Namespace (Single DAG)

(B)  Active/Passive model with different namespaces (Single DAG)

(C) Active/Active Model with Different Namespaces (2 DAGs).

I am Just Curious to know is there any other model DAG that can be proposed apart from above mentioned Designs in terms of both Namespace and Database Active copy Location.

Also can you also put some light and clarify whether we can haveActive/Active Model with Shared Namespace (Single DAG). I have read it is supported in exchange 2013, if so can we do the same in Exchange 2010 as well. If not what makes this design different in exchange 2010 v/s exchange 2013. How can we achieve this design in exchange 2013?

I got a good article on above scenarioshere but I have some terms or paragraphs bit confusing. Please help me to understand the bold lines in below paragraph.

Since we typically only have active users connecting to the primary datacenter (at least the majority of the users connect to this datacenter unless a site failover occurs), the autodiscover record (autodiscover.exchangelabs.dk) in external DNS points to the load balancer in the primary datacenter. The internal “AutoDiscoverServiceInternalUri” on the CAS servers in the primary datacenter has been configured with a value of https://mail.exchangelabs.dk/autodiscover/autodiscover.xml, and the same goes for the CAS servers in the failover datacenter. Now you could choose to point the AutoDiscoverInternalUri on CAS servers in the failover datacenter at “https://failover.exchangelabs.dk/autodiscover/autodiscover.xml” but you can easily up on in a situation where SCP’s aren’t reachable during a site failover. Also, cross-site traffic caused by Autodiscover have a minor impact on the WAN link since autodiscover requests consists of small XML based text files.

Also inActive/Passive model with different namespaces (Single DAG) or  Active/Active Model with Different Namespaces (2 DAGs) model do we still repoint EWS,OA,EAS etc. web service records in public DNS. If yes what should be their value (please referComplete Site failoverSegment in Above URL)

 it would be very helpful if you could provide any detailed Design diagram as mentioned in URL to understand the things better. or any Technet Articled with well description

Thanks in advance 

Regards

Aanand Singh

Regards, Aanand Singh