A. In Exchange 2007, LCR allows two copies of the same mailbox database to be hosted on a single server. LCR provides protection against mailbox corruption by replaying transaction logs into a second copy. In Exchange 2010, Cluster Continuous Replication and Standby Continuous Replication were unified into a single Database Availability Group (DAG) model, which allows 16 servers per DAG, with multiple copies of each database. However, LCR wasn't included.
You can't have more than one copy of the same database on a single node with DAG, so the LCR functionality you have in Exchange 2007 no longer exists in Exchange 2010.Related Reading:
- Q. What is the mailbox high availability solution in Exchange 2010?
- Q. With Microsoft Exchange Server 2010 coming, should I use single copy clusters or local continuous replication when planning my high availability for Exchange 2007?
- Exchange 2007 Now or Exchange 2010 Later?
- A First Look at Exchange 2010
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