Handling Large Mission-Critical Environments

Mission-critical environments often require that databases be available continuously, or for extended periods of time with minimal down-time for maintenance tasks. Therefore, the duration of unexpected situations, such as a hardware failure, that require databases to be restored needs to be kept as short as possible. Additionally, mission-critical databases are often large, requiring longer periods of time to back up and restore. Microsoft® SQL Server™ offers several methods for increasing the speed of backup and restore operations, thereby minimizing the effect on users during both operations.

The following practices will help:

• Use multiple backup devices simultaneously to allow backups to be written to all devices at the same time. Similarly, the backup can be restored from multiple devices at the same time.
  
  
• Use a combination of database, differential database, and transaction log backups to minimize the number of backups that need to be applied to bring the database to the point of failure.
  
  
• Use file and filegroup backups and transaction log backups, which allows only those files that contain the relevant data, rather than the entire database, to be backed up or restored.
  
  
• Use snapshot backups which reduce backup and restore time to a minimum. Snapshot backups are supported by third party vendors. For more information, see Snapshot Backups.