Recommended configurations for Exchange

The following are recommendations for configuring Exchange for optimal protection and recovery:

Recommendation	Description
Disable circular logging	This allows you to run differential or incremental backups of Exchange. If you do not disable circular logging, only full backups are supported. See About the circular logging setting for Exchange for more information.
Do not allow the physical or virtual machine hosting the Exchange server to be a domain controller	This allows much simpler and faster Exchange restores since you will not first have to restore Active Directory on the same server.
Make sure that the physical or virtual machine hosting the Exchange server is a member of a domain that has at least two domain controllers	This allows faster recovery. Active Directory information is replicated if there is more than one domain controller, which means that if one domain controller fails the other can be used to recover missing transactions after the failed domain controller is restored.
Separate transaction log files from the Exchange server database	Exchange performs much more efficiently if the Exchange database and transaction logs are placed on different physical storage devices. In addition, by separating these two important components, recovery of failed storage is eased.
Disable the write cache on any hard drive or RAID adapters being used in the system that is hosting the Exchange server

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