NetVault SmartDisk 11.4.5 - Installation Guide

10% = Weekly Change Rate

10 GB = Size of Daily Backups

100 + ((100 * 0.1) * 12) + (10 * (6*4)) =

100 + ((10) * 12) + (10 * (24)) =

100 + (120) + (240) = 460GB

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If the OS is 64-bit:

460/15360 = .029

Rounded Up to Next Whole Number = 1 NetVault SmartDisk Instance

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If the OS is 32-bit:

460/1843.2 = 0.25

Rounded Up to Next Whole Number = 1 NetVault SmartDisk Instance

Ingest Rate > Network Bandwidth

The NetVault SmartDisk Ingest Rate is the rate at which data can be streamed into NetVault SmartDisk. Because data streams into the NetVault SmartDisk Instance through a user-defined port, the network bandwidth limits the speed at which data can be streamed. To ensure that all backups targeted to a NetVault SmartDisk Instance can complete during the backup window, divide the required ingest rate by the Maximum Sustained Network Bandwidth to determine the number of required NetVault SmartDisk Instances. Use the following calculation to determine the number of NetVault SmartDisk Instances based on the NetVault SmartDisk Ingest Rate and Network Bandwidth:

((Size of Weekly Full Backups * 1024) / (Number of Hours in Backup Window* 60 * 60))

/ Maximum Sustained Network Bandwidth

8 = Number of Hours in Backup Window

100 = Maximum Sustained Network Bandwidth (MB/Sec)

((100 *1024) / (8 * 60* 60)) / 100 =

((102400) / (28,800)) / 100 =

3.55 / 100 = .035

Rounded Up to Next Whole Number = 1 NetVault SmartDisk Instance

Deduplication Rate < Ingest Rate

The NetVault SmartDisk Deduplication Rate is the rate at which NetVault SmartDisk deduplicates data. If NetVault SmartDisk deduplication is configured to run during the backup, the NetVault SmartDisk Deduplication Rate must be greater than or equal to the Ingest Rate to ensure that the deduplication process completes before the next weekly backup window begins.

Use the following to estimate the Deduplication Rates:

Determine the Single Core Deduplication Rate:


Hardware	Speed
24 to 36 Month Old Intel Core 1, AMD Athlon or Intel Celeron	10 to 20 MB/sec
12 to 24 Month Old Core 2 Duo, AMD Quad Core Opteron or Dual Core Xeon	20 to 40 MB/sec
0 to 12 Month Old Desktop or Server Core 2 Duo, Quad Core Xeon or Quad Core AMD	40 MB/sec or more

Multiply the Single Core Deduplication Rate by the number of Cores.

Use the following calculation to determine the number of NetVault SmartDisk Instances based on the Deduplication Rate and Ingest Rate:

(((Size of Weekly Full Backups) + (Size of Daily Backups * Number of Daily Backups between Weekly Full Backups)) * 1024)

/ (Number of Seconds in Deduplication Window for 6 Days) / Deduplication Rate

10% = Weekly Full Backup Growth Rate

10 GB = Size of Daily Backups

24 = Number of Hours in Daily Deduplication Window

50 = Deduplication Rate (MB/Sec)

(((100) + (10 * 6)) * 1024) / (24 * 6 * 60 * 60)) / 50 =

(((100) + (60)) * 1024) / (518400)) / 50 =

((160*1024)/518400)/50) =

(163840/518400)/50) = .0063

Rounded Up to Next Whole Number = 1 NetVault SmartDisk Instance

Determining the required number of NetVault SmartDisk Instances

The maximum result for the following three calculations determines the number of NetVault SmartDisk Instances that must be deployed:

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Unique Data Size > 15 TB for 64-bit OS and > between 1.8 TB and 2.5 TB for 32-bit OS, depending on the OS

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Ingest Rate > Maximum Sustained Network Bandwidth

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Deduplication Rate < Ingest Rate

Unique Data Size > OS Bit Limit = 1 NetVault SmartDisk Instance

•

•

Ingest Rate > Network Bandwidth = 1 NetVault SmartDisk Instance

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Deduplication Rate < Ingest Rate = 1 NetVault SmartDisk Instance

The maximum result is one NetVault SmartDisk Instance; therefore, only one NetVault SmartDisk Instance is required in this example.

Determining the number of nondeduplicated NetVault SmartDisk Instances

A single factor determines the number of Nondeduplicated NetVault SmartDisk Instances:

Ingest Rate > Maximum Sustained Network Bandwidth

Ingest Rate > Network Bandwidth

((Size of Weekly Full Backups * 1024) / (Number of Hours in Backup Window* 60 * 60))

/ Maximum Sustained Network Bandwidth

8 = Number of Hours in Backup Window

100 = Maximum Sustained Network Bandwidth (MB/Sec)

((100 *1024) / (8 * 60* 60)) / 100 =

((102400) / (28,800)) / 100 =

3.55 / 100 = .035

Rounded Up to Next Whole Number = 1 NetVault SmartDisk Instance

Calculating the total required physical disk space for licensed capacity

NetVault SmartDisk is licensed based on the front-end terabytes (TBs) or amount of data to be protected from all source machines. However, in Deduplicated NetVault SmartDisk Instances, Licensed Capacity does not match Physical Capacity or physical disk space. This mismatch is because the NetVault SmartDisk Deduplication Option packs up to 12 times more protected data into the same storage area for a 92 percent reduction in the storage footprint.

Determining the capacity for deduplicated NetVault SmartDisk Instances

A Deduplicated NetVault SmartDisk Instance can have a combination of both Deduplicated and Nondeduplicated data. In this configuration, calculating the total Physical Capacity or physical disk space is achieved by calculating the Physical Capacity for the Deduplicated Backups, calculating the Physical Capacity for the Nondeduplicated Backups, and adding the sums.

Deduplicated backups

The Physical Capacity or physical disk space required for Deduplicated Backups in Deduplicated NetVault SmartDisk Instances is equal to the Size of Weekly Full Backups plus the Unique Data Size. Use the following formula to calculate it:

(Size of Weekly Full Backups) +

(Size of Weekly Full Backups + ((Size of Weekly Full Backups * Weekly Change Rate)

* Weekly Full Backup Retention Period)

+ (Size of Daily Backups * (Number of Daily Backups between Weekly Full Backups

* Daily Backup Retention Period)))

100 GB = Size of Deduplicated Weekly Full Backups across all servers

10% = Weekly Change Rate

10 GB = Size of Deduplicated Weekly Daily Backups

100 + (100 + ((100 * 0.1) * 12) + (10 * (6*4))) =

100 + (100 + ((10) * 12) + (10 * (24))) =

100 + (100 + (120) + (240)) = 560GB

Nondeduplicated backups

Use the following formula to calculate the Physical Capacity or physical disk space required for Nondeduplicated Backups in a Deduplicated NetVault SmartDisk Instance:

(Size of Nondeduplicated Weekly Full Backups * Weekly Full Backup Retention Period)

+ (Size of Nondeduplicated Daily Backups * (Number of Daily Backups between Full Backups * Daily Backup Retention Period in Weeks))

10 GB = Size of Nondeduplicated Weekly Full Backups

1 GB = Size of Nondeduplicated Daily Backups

(10 * 12) + (1 * (6 * 4)) =

(120) + (1*(24)) =

120 * 24 = 144GB

Total Required Disk Space = Deduplicated Backup Disk Space + Nondeduplicated Backup Disk Space

560 GB + 144 GB = 704 GB

The Total Required Disk Space is divided into the Staging Store and the Chunk Store. If you intend to use different file systems or disks for the Staging Store and the Chunk Store, it is important to know how much of the Total Required Disk Space is allocated to the Staging Store versus the Chunk Store. Use the following calculations to determine this amount.

Calculating Staging Store size

The amount of time a Deduplicated Backup remains in the Staging Store is different than the amount of time a Nondeduplicated Backup remains in the Staging Store. Therefore, to determine the total disk space required for the Staging Store, you must calculate the size required for both Deduplicated Backups and Nondeduplicated Backups.

Total Staging Store Disk Space = Deduplicated Backup Disk Space + Nondeduplicated Backup Disk Space

Deduplicated backups

During the NetVault SmartDisk Deduplicated Backup process, backups are initially streamed to the Staging Store where they remain until the deduplication process is finished. The Staging Store must be large enough to hold all the Deduplicated Backups while they await deduplication.

If the deduplication window overlaps the backup window, deduplication and backups occur at the same time. Each backup starts deduplicating after the backup job is finished. Also, large backups are broken into 400 GB segments. Each segment starts to deduplicate after it is received, even if the backup stream is still being streamed to the Staging Store. Therefore, the Staging Store only requires space to hold some portion of the total backup size. If the Staging Store runs out of space, backups pause until space becomes available, such as when a deduplication operation finishes.

The maximum disk space required for the Staging Store is equal to the Size of the Weekly Full Backups.

Nondeduplicated backups

Backups that are not deduplicated are streamed into the Staging Store, where they remain until they are retired. Therefore, calculating the size of the Staging Store for Nondeduplicated Backups is identical to calculating the required physical disk space for Nondeduplicated Backups in a Deduplicated NetVault SmartDisk Instance.

(Size of Nondeduplicated Weekly Full Backups * Weekly Full Backup Retention Rate)

+ (Size of Nondeduplicated Daily Backups * (Number of Daily Backups between Full Backups * Daily Backup Retention Period in Weeks))

10 GB = Size of Nondeduplicated Weekly Full Backups

1 GB = Size of Nondeduplicated Daily Backups

(10 * 12) + (1 * (6 * 4)) =

(120) + (1*(24)) =

120 * 24 = 144GB

Calculating Chunk Store size

The amount of physical disk space required for the Chunk Store is equal to the Unique Data Size. To calculate the Unique Data Size or the size of the Chunk Store, use the following formula:

Size of Weekly Full Backups + ((Size of Weekly Full Backups * Weekly Change Rate)

* Weekly Full Backup Retention Period)

+ (Size of Daily Backups * (Number of Daily Backups between Weekly Full Backups

* Daily Backup Retention Period))

10 GB = Size of Daily Backups