vRanger 7.8 - Integration Guide for NetVault SmartDisk

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

Example:

100 GB = Size of Weekly Full Backups

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:

1	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

2	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

Example:

100 GB = Size of Weekly Full Backups

10% = Weekly Full Backup Growth Rate

10 GB = Size of Daily Backups

6 = Number of Daily Backups between Full 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:

•	Unique Data Size > 15 TB for 64-bit OS and > 5 TB for 32-bit OS

•	Ingest Rate > Maximum Sustained Network Bandwidth

•	Deduplication Rate < Ingest Rate

Example:

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

•	Ingest Rate > Network Bandwidth = 1 NetVault SmartDisk Instance

•	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 required disk space for NetVault SmartDisk Instances

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.

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 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, vRanger backups fail.