I recently came into a company with an Exchange 2010 sp1 environment where there are two data centers in two different subnets (10.70.62.0 and 10.80.56.0)
Each datacenter has 2 mailbox servers (4 servers total) but their plan was to have only enough storage space to host 1/2 of the databases on each server. So instead of server 1, 2, and 3 being copies of each other, ServerA is a copy of ServerA and ServerB
is a copy of ServerB
Server - Databases
Site1mbA - Primary Database copy 1-10
Site1mbB - Primary Database copy 11-20
Site2mbA - Secondary Database copy 1-10
Site2mbB - Secondary Database copy 11-20
Normally if there were enough storage space I would keep a copy on each server and replicate within 1 DAG.
However since not all the databases are on each member server do I need to use 2 DAGS? 1st for Site1mbA & Site2mbA and 2nd for Site1mbB & Site2mbB
I feel I would need the 2 DAG's because with 1 DAG if Site1mbA server went offline the DAG couldn't switch to the Failover Cluster IP for Site2 because there are still active mailboxes in Site1 on Site1mbB.
Does that make any sense or am I over complicating it?
Thanks!