NetVault SmartDisk 11.4.5 - Installation Guide

Deduplicating similar data together

You can increase deduplication ratios by targeting backups from the same database, file system, or application to the same NetVault SmartDisk Instance. When a backup is deduplicated and a previous backup from the same database, file system, or application has already been deduplicated by the NetVault SmartDisk Instance, only the unique or new Chunks that did not exist in the previous backup have to be stored in the Chunk Store. If a previously deduplicated backup does not exist in the NetVault SmartDisk Instance, most of the backup is considered unique data; this issue increases the number of unique Chunks that have to be stored in the Chunk Store.

When targeting backups to NetVault SmartDisk Instances, deduplication ratios decline if backups are targeted to random NetVault SmartDisk Instances. Quest recommends that you target backups from the same database, file system, or application to the same NetVault SmartDisk Instance.

Separating vs. combining deduplicated data in NetVault SmartDisk Instances

An entire NetVault SmartDisk is licensed as either nondeduplicated or deduplicated capacity. When the data stored in NetVault SmartDisk is a combination of nondeduplicated and deduplicated data, two deployment options are available:

When the data targeted for NetVault SmartDisk is a combination of nondeduplicated and deduplicated data, you can create multiple NetVault SmartDisk Instances: one for nondeduplicated data and one for deduplicated data. In this case, the Nondeduplicated Instance is licensed as NetVault SmartDisk Capacity and the Deduplicated Instance is licensed as NetVault SmartDisk Capacity with Deduplication Option.

This option lets you purchase the Deduplication Option for only the capacity that should be deduplicated. In this type of deployment, it is your responsibility to ensure that the correct NetVault SmartDisk Instance is targeted for backup. This deployment ensures that data intended for deduplication is deduplicated and that data not intended for deduplication is stored as nondeduplicated data.

When the data targeted for NetVault SmartDisk is a combination of nondeduplicated and deduplicated data, you can create a single NetVault SmartDisk Instance.

This option requires that you purchase the Deduplication Option for the entire NetVault SmartDisk Instance, including the capacity for the backups that are not deduplicated.

Determining the size of the NetVault SmartDisk deployment

The second step in defining your NetVault SmartDisk Deployment Strategy is to determine the size of your NetVault SmartDisk Deployment. To determine the size of your deployment, complete the following steps, which are described in detail in subsequent sections:

Calculating NetVault SmartDisk license capacity

NetVault SmartDisk is licensed by front-end terabytes (TBs). A front-end TB is the aggregate amount of data that you want NetVault SmartDisk to protect from all source or client machines that are targeting a single NetVault SmartDisk Instance. A front-end TB is measured by the amount of storage capacity occupied on the source storage by files that are to be backed up; this measurement is based on the capacity consumed before data reduction that might be achieved by using the optional NetVault SmartDisk Deduplication Option. Front-end source data can include OS-related data, file system data, database data, application data, and so on.

Because a front-end TB is the total amount of data that you intend to back up from all client or source storage devices, it helps you determine how much data you back up to NetVault SmartDisk. Front-end TBs are only counted once; it does not matter how many times you back up the same set of data or how long you retain each version of the backup data.

NOTE: Only the data from a source machine that is being sent to NetVault SmartDisk must be included in the licensed capacity. If you are targeting other devices, such as real tape media, for some of the data residing on a source machine, that data does not count towards front-end capacity for NetVault SmartDisk licensing.

NetVault SmartDisk can accept backup data from multiple servers. You can also deploy multiple NetVault SmartDisk Instances, which can act as targets for clients connected to multiple servers. When calculating the licensed capacity for a NetVault SmartDisk Instance, you must include the capacity across all clients or sources targeting that NetVault SmartDisk Instance.

NetVault SmartDisk Licensed Capacity is not based on the following: