Mail is now firmly established as a mission-critical application for many businesses, and more than 60% of enterprises use Microsoft Exchange for their corporate email, according to Gartner. This widespread corporate adoption of Microsoft Exchange, coupled with its mission-critical nature and growing electronic discovery requirements, make protecting it a more complicated proposition than just performing simple backups and recoveries.
Recovery time objectives (RTOs), recovery point objectives (RPOs) and cost are what drive the level of protection businesses provide for their Microsoft Exchange environments. Companies that can withstand outages of up to one day may consider the use of the free Microsoft Windows Server 2003 NTBackup utility to protect their Microsoft Exchange data stores. But enterprises that need their Exchange storage groups backed up and recovered in seconds or minutes, either onsite or offsite, may need a combination of products to deliver the appropriate levels of recovery and availability they require
Backup products for Exchange fall into three classes:
- Backup software with specific Exchange agents
- High-availability software and/or appliances
- Archival software
Backup software products first install their client on the Exchange server and then install an agent that interacts directly with the Exchange database. The level of granularity the agent provides for the backup and restore of individual components of the Exchange database separates average backup software products from above average ones.
The Exchange agents of the big three backup software products--EMC NetWorker, IBM Tivoli Storage Manager (TSM) and Symantec Veritas NetBackup--each support full, differential, incremental and synthetic backups of the Exchange database, and permit admins to select specific Exchange storage groups to back up and restore. The strengths of these products lie in their scheduling and policy/media management abilities, which are desirable for firms that need to schedule their Exchange backups centrally or perform storage-area network-based backups using multiple media types.
But there's some question about whether firms need all of these features, which may be cumbersome to manage and use. For instance, IBM's TSM requires admins to first recover the entire storage group, mount the storage group in Exchange 2003 as a Recovery Storage Group, identify the message or mailbox that needs to be restored, and then copy it to the appropriate location in the production mail store. Exchange 2000 recoveries are even more time-consuming because admins may need to stop the entire Exchange 2000 server to recover specific messages or mailboxes.
Instead, support for "brick-level" recoveries of individual items like email messages are part of the standard by which backup software should be measured. These allow admins to select and restore one email at a time directly into the production mail store without first recovering the entire storage group.
Several backup software products, including BakBone Software's NetVault:Backup, CA's ARCserve Backup and Symantec's Veritas NetBackup, offer support for brick-level recoveries, but users may need to select specific configuration options within the backup software to obtain them. CA's ARCserve offers both object-level and full backup options.