The following best practices apply to deduplication disk storage devices:

• Use a dedicated volume for a deduplication disk storage device.

• Ensure that the volume you use for a deduplication disk storage device has enough space to hold data from multiple servers. Symantec recommends that you use a dynamic volume that can grow as needed.

• Ensure that the Backup Exec server on which you create a deduplication disk storage device has the appropriate amount of RAM. The minimum amount of RAM is 8 GB, which supports up to 5 TB of deduplicated data.

  Note:

  This minimum requirement is in addition to the minimum requirements for Backup Exec.

  For more than 5 TB of data, use the following calculation to determine the required amount of RAM:

  1.5 GB x N, where N equals the number of TB of storage in the deduplicated volume. Up to 32 TB of data is supported.

  Example: Use the following equation to calculate the required amount of RAM for 10 TB of data:

  1.5 x 10 = 15 GB RAM

• Perform regular backups of the deduplication disk storage device to removable media. Create this job separately from the backup job that you use to protect the rest of your system. In the backup selection list, the Backup Exec Deduplication Storage node is located under the User Data node under Shadow Copy Components.

• Use a dedicated logon account when creating a deduplication disk storage device.

• Use the spauser.exe utility if you have to change the password for the Backup Exec logon account that you specified when you created a deduplication storage folder. When you specify a logon account for a deduplication disk storage device, an additional user account is created for the deduplication components with the same user name and password. However, if you change the credentials for the Backup Exec logon account, the credentials for the additional user account are not changed automatically. You must use the spauser.exe utility to update the password for the additional user account. This account is known as the "User 1" account when you use the spauser.exe utility to view a list of user names that are associated with the deduplication disk storage device. The passwords must be kept synchronized to ensure that the deduplication disk storage device is accessible after services are restarted, and to facilitate recovery of the deduplication disk storage device after a system failure.

• Exclude the deduplication disk storage device from your antivirus scans. If an antivirus scanner deletes or quarantines the files from the deduplication disk storage device, access to the deduplication disk storage device may be disabled.

• Do not use Backup Exec's Simplified Disaster Recovery (SDR) to recover local data from the local deduplication disk storage device. SDR recovery from deduplication disk storage devices is supported for remote resources only.

• Perform a duplicate backup job so that you have redundant backups of the data in your deduplication disk storage device. This method is preferred over performing full backups using the deduplication writer because this method is easier to control.

• Review the tech note titled "Getting the most out of the Deduplication Option and Deduplication Storage Folders" for more details about using deduplication disk storage devices. The tech note is available from the following link:

  http://www.symantec.com/docs/TECH142668

The following best practices apply to using deduplication with SQL:

• Set the option Use snapshot technology as a backup job property for the SQL backup job. This option allows data to be deduplicated in the most effective way.

• Use Microsoft SQL Server Management Studio to restrict SQL's use of physical memory. This option can be set for each SQL instance by selecting Properties > Memory. Restricting SQL to use 85% to 90% of total physical memory can prevent a situation in which backup rates may be reduced to 10% of the expected rate due to memory restrictions.

The following best practices help you to use the Deduplication Option effectively:

• Use client-side deduplication for all deduplication jobs, except in the following situations:

  • The remote computer has limited or no resources available to dedicate to the deduplication process during backup jobs.

  • Your environment contains multi-server configurations of Microsoft SharePoint servers, Microsoft Exchange 2012 DAG servers, and Symantec Enterprise Vault servers.

  • You want to back up virtual machines with the Agent for VMware.

• Ensure that the appropriate third-party vendor plug-in is installed for an OpenStorage Technology (OST) device and exists in the Backup Exec directory. The plug-in enables Backup Exec to detect the OST device and display the device in the server list.

• Inventory and catalog the media when you restore from an optimized duplication backup.

• Disable RAID caching on the disk where the deduplication disk storage device is located.

• Verify all backup data.

• Apply the following Microsoft hot fixes to improve performance:

  http://support.microsoft.com/kb/979612

  http://support.microsoft.com/kb/982383