Can a CAS server that participates in a CAS Array be on a different DAG?

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Ok.  I have two sites.  Each site will have two multi-role Exchange 2010 SP2 servers.  I would like to have two two member DAGs (with DAC) because both sites have active users, and both sites would need to be protected from hardware failures/disasters.  The sites are connected by low latency, high bandwidth VPN.  If the connection between the sites fails, both sites need to be able to continue to have access to their mailboxes.  

My questions is this: can a server be a member of both a CAS array and a DAG, even if the CAS array is for a mailbox database that's on a different DAG?  

Below is a basic diagram of my design.  Will it work?  Are there any glaring problems to my design?  Any potential for problems?

Thanks in advance!
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Commented:
Hi
the following link would help to understand about DAG. Also  the DAG only work with mailbox database server role hence CAS should work with all the exchange server with in an exchange organization.

http://technet.microsoft.com/en-us/library/dd979799.aspx

Commented:
Yes you can have CAS array member of DAG
- For CAS array settings, yes you can have a CAS on a member of other DAG.

- In case of a site failure, you have to manually activate the DR it cannot be an automated process.

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Commented:
abdulalikhan,

can you elaborate on "- In case of a site failure, you have to manually activate the DR it cannot be an automated process."?

thanks!
In Case of Site '1' failure, DAG 'A' will be down as the majority is down but DAG 'B' will continue to work as Site '2' has the majority. To mount the databases for DAG 'A' and force clients who are member of DAG 'A' to use site 2 CAS you need to manually activate the DR. This cannot be an automated process.

I am sending links which tell the complete details of the DAG, failover and failback scenario. Jump to the part number for Failover and failback scenarios.

http://www.msexchange.org/articles_tutorials/exchange-server-2010/management-administration/planning-deploying-testing-exchange-2010-site-resilient-solution-sized-medium-organization-part1.html

http://port25.wordpress.com/2009/12/03/how-to-manage-a-datacenter-failure-or-disaster-recovery-scenario-in-exchange-2010-part-1/

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