Creating a Transparent RAID array

Pre-requisite

Preparing & Registering disks for Transparent RAID

About the test setup

For the purpose of this tutorial, a demo virtual machine system has been setup with 5 virtual disks.
Each disk is 2GB in size. Note that Transparent RAID has been tested on systems with tens of terabytes of storage disks.
The purpose of using such small disks in this tutorial is to speed up the various task executions in order to quickly create this tutorial.
Computing parity or running a verification test on a storage array of 100TB would take many hours.
To see Transparent RAID running on very large arrays, please visit the showcase gallery.

Test setup

In our test setup, we have 5 disks; 3 of which have been formatted with volumes as shown below (E, F, and G).
The two other disks will be used for parity and have been left non-formatted.
1. Explorer view of test disks

Here is another view of the test disks as shown from the Web UI and in the Windows Disk Manager.
2. Disk Manager view of test disks


Creating a Transparent RAID Configuration

1. Right-Click on the “RAID Configurations” node, and select to create a RAID.
3. Create a new tRAID config

2. For RAID type, select “Transparent RAID”.
4. Select tRAID as RAID type

3. Enter a display name for the RAID configuration.
5. Enter a display name for the config

4. The created RAID configuration will be shown under the “RAID Configurations” node.
Open the created RAID configuration
6. Created tRAID config

5. Click on the “Add Unit of Risk (UoR)” to start adding disks to the created configuration.
7. Add UoR

6. First select a registered disk.
8. Pick UoR Disk

7. Then, specify its purpose (which of data disk or parity disk it is purposed for).
It is recommended that you add your parity disk(s) first as additional options might be presented to you based on the number of configured parity disks.
9. Add PPUs First

8. For instance, multi-PPU configurations support the concept of placeholders.
Placeholders are required to enable RAID Expansion and RAID Contraction in multi-PPU configurations.
If you have an array you intend to grow to say 10 data disks, but you only currently have 5 data disks, you would add the 5 data disks and then add 5 placeholders for the future disks.
10. Placeholder for Multi-PPUs

9. Here is an example of a multi-PPU configuration with a placeholder.
11. Multi-PPU Config

10. For the remainder of this tutorial, however, we will focus on a single PPU configuation.
The remaining DRU and PPU will be added when we cover the topic of RAID Expansion.
12. Single PPU Config

11. Tooltips are available to provide additional info on the UI elements.
13. RAID Config Panel Overview

12. Click on the “Start” button. Normally, this would start the array. However, because the array has not been initialized, we will be prompted to initialize the array.
14. RAID Init Prompt

13. Several initialization options are presented to us.

  • The “Do nothing” is to be used to initialize the array without computing parity. This can be useful for cases where we are simply recreating the configuration for an existing array. Another purpose for this option is to delay the parity computation till after the RAID as been deployed to minimize down time. With the normal RAID initialization process, you won’t have access to your data till the parity computation is complete. In contrast, with this option, one can deploy the array making all data available right away for use (read/write) and then have the parity computation take place in the background by running the Verify/Sync task later on.
  • “Verify & Sync” is useful for cases where we think the parity data might be valid and we would like the initialize the array offline by verifying the parity data and re-writing it where there is mismatch with the data.
  • “Create RAID Parity” is the standard option and the recommended option.
  • “Format Drives” is not available for Transparent RAID initialization.

15. RAID Init Options

14. Select to “Create RAID Parity”. You will be prompted to confirm the task execution.
16. Create RAID Parity task

15. The task will run and complete some time later. On large arrays this could take many hours.
17. Create RAID Parity task - Completed


What’s next?

Publishing (starting) a Transparent RAID array

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