Create RAID Group

Overview

This function creates a RAID group.

A RAID group is a group of drives that configure a RAID level.

Refer to Detailed Information for RAID Levels, Drives, and Volumes for details.

The Maximum Number of RAID Groups for Each Model

The maximum number of RAID groups is determined by the number of installed drives.

The maximum number of RAID groups is half the maximum number of installed drives (when configuring each RAID group with the minimum configuration of two drives).

The following table shows the maximum number of RAID groups for each model.

Model The maximum number of RAID groups

ETERNUS DX600 S6

480

ETERNUS DX900 S6

 1152
ETERNUS DX8100 S6

12
ETERNUS DX8900 S6

2304

Drive Combinations That Can Configure a RAID Group

The following table shows the drive combinations that can configure a RAID group.

  Online Nearline SSD NVMe SSD Online SED Nearline SED SSD SED NVMe SSD SED
Online OK OK (but not recommended) NG NG NG NG NG NG
Nearline OK (but not recommended) OK NG NG NG NG NG NG
SSD NG NG OK NG NG NG NG NG
NVMe SSD NG NG NG OK NG NG NG NG
Online SED NG NG NG NG OK OK (but not recommended) NG NG
Nearline SED NG NG NG NG OK (but not recommended) OK NG NG
SSD SED NG NG NG NG NG NG OK NG
NVMe SSD SED NG NG NG NG NG NG NG OK

OK: RAID groups can be created    OK (but not recommended): RAID groups can be created, but not a recommended configuration   NG: RAID groups cannot be created

Settings

In this screen, create a RAID group.

There are two methods to create RAID groups: automatic drive selection and manual drive selection.

New RAID Group

Input the name of the RAID group that is to be newly created and select the create mode.

Item Description Setting values

Name

Input a RAID group name that is to be created.

When creating a single RAID group, an existing RAID group name cannot be used.

Up to 16 alphanumeric characters,

symbols (except "," (comma) and "?"),

and spaces

Create Mode

Select the create mode of the RAID group.

  • Automatic

    Select a drive to create a RAID group automatically.

  • Manual

    Select a drive to create a RAID group manually.

Automatic

Manual

Automatic Setting

Item Description Setting values

Number of RAID Groups

Input the number of RAID groups that are to be created.

When creating multiple RAID groups at a time, the new RAID groups are named automatically. Refer to Naming Conventions for Creating RAID Groups for details.

Refer to The Maximum Number of RAID Groups for Each Model for details about the setting values.

0 (Default)

Drive Type

Select the type of drive that configures a RAID group from the list box.

Only the drives that are installed in the storage system are displayed.

Caution
  • If drives that satisfy all of the following conditions are installed in the storage system, select the drives manually.

    • The drive types are the same

    • The drive capacities are the same

    • The sector format (AF-compliant/non-AF-compliant) is different

Refer to Drive Type.

RAID Level

Select the level of RAID group that is to be created.

Caution

  • Several restrictions apply to RAID groups and volumes in the "RAID6-FR" type RAID group. Refer to Restrictions for RAID6-FR for details.

  • Several restrictions apply to RAID groups that are created with "RAID5+0". Refer to Restrictions for RAID5+0 for details.

Refer to RAID Level.

Select Drives

Select the requirements that are given priority when creating a Fast Recovery RAID group with automatic drive configuration.

This item is available only when the RAID level is "RAID6-FR".

Minimize number of using drives

Prioritize rebuild rate

Minimum Capacity per RAID Group

Input the RAID group capacity that is to be created and select the units of capacity.

A RAID group is automatically created with a capacity of the entered value or higher.

Numeric characters

Unit: TB/GB/MB

Naming Conventions for Creating RAID Groups

  • When creating multiple RAID groups at a time, a name is automatically added to a RAID group with the specified "Name" and a suffix number "x" (serial numbers starting with "0").

    (Example) Specified RAID group name: RAIDGroup_aaaa (14 characters) → Name for created RAID group: RAIDGroup_aaaa0, RAIDGroup_aaaa1, etc.

  • When the RAID group name including the suffix number "x" has more than 16 characters, the excess number of characters is deleted from the "Name", starting with the last character and a suffix number "~x" will be added. Then, the name will contain only 16 characters.

    (Example) Specified RAID group name: RAIDGroup_aaaabb (16 characters) → Name for created RAID group: RAIDGroup_aaaa~0, RAIDGroup_aaaa~1, etc.

  • When a RAID group name including the suffix number already exists, the suffix number is increased by one (+1). The suffix number is increased by one (+1) until no RAID group names overlap.

Manual Setting

Item Description Setting values

RAID Level

Select the level of RAID group that is to be created.

Caution

  • Several restrictions apply to RAID groups and volumes in the "RAID6-FR" type RAID group. Refer to Restrictions for RAID6-FR for details.

  • Several restrictions apply to RAID groups that are created with "RAID5+0". Refer to Restrictions for RAID5+0 for details.

Refer to RAID Level.

Controlling CM

Specify the Controlling CM of the RAID group to be created.

"Automatic" and the normal CM number ("CE#n CM#n" or "CM#n") that is installed are displayed as options.

Select "Automatic" for normal operations. When "Automatic" is selected, the Controlling CM that is to be allocated is determined by the RAID group number. Refer to Automatic Controlling CM Setting for details.

For the ETERNUS DX900 S6 or the ETERNUS DX8900 S6

Automatic

CE#n CM#n

For the ETERNUS DX600 S6 or the ETERNUS DX8100 S6

Automatic

CM#n

Fast Recovery Configuration

Select the drive configuration for a Fast Recovery RAID group.

Select the drive configuration from "No. of drives in the configuration", "capacity efficiency", and "rebuilding speed" according to your environment. Refer to Drive Configuration for Fast Recovery RAID Groups for details. The more redundant sets there are, the faster the rebuilding becomes.

This item is blank when the RAID level is not "RAID6-FR".

(3D+2P)x2+1HS

(4D+2P)x2+1HS

(6D+2P)x2+1HS

(9D+2P)x2+1HS

(12D+2P)x2+1HS

(5D+2P)x4+1HS

(13D+2P)x2+1HS

(8D+2P)x3+1HS

(4D+2P)x5+1HS

(3D+2P)x6+1HS

Blank

D: Data drives

P: Parity drives

HS: Hot Spares

Minimum Capacity per RAID Group

The capacity of RAID group that is to be created is displayed.

The "Minimum Capacity per RAID Group" is automatically calculated from the selected RAID level and drives.

  

Drive Configuration for Fast Recovery RAID Groups

The drive layout in the storage system is the same as "RAID6". When using automatic configuration, the drive configuration that satisfies the specified capacity is determined according to the following order.

No. of drives in the configuration

(per RAID group)

 Redundant sets + HS (*1)

Capacity efficiency (*2)

(%)

Rebuilding speed (*3)

(Rate)

 Number of data drives Selection order when configuring automatically
"Minimize number of using drives" is selected "Prioritize rebuild rate" is selected
11 (3D+2P)x2+1HS 54.5 2.20 6 1 5
13 (4D+2P)x2+1HS 61.5 2.17 8 2 6
17 (6D+2P)x2+1HS 70.6 2.13 12 3 7
23 (9D+2P)x2+1HS 78.3 2.09 18 4 8
29 (12D+2P)x2+1HS 82.8 2.07 24 5 9
31 (13D+2P)x2+1HS 83.9 2.06 26 6 10
31 (3D+2P)x6+1HS 58.1 6.20 18 Not selected 1
31 (4D+2P)x5+1HS 64.5 5.17 20 Not selected 2
29 (5D+2P)x4+1HS 70.0 4.14 20 Not selected 3
31 (8D+2P)x3+1HS 77.4 3.10 24 Not selected 4
*1  :  Fast Recovery RAID groups are described as "Redundant sets + HS".

     RAID6 ((Number of data drives (D) + Number of parity drives (P)) × Number of redundant sets + Number of hot spares (HS))

                             ↑

                         Redundant sets

     (Example) "RAID6 ((3D+2P)x2+1HS)" is described as "(3D+2P)x2+1HS".
*2  :  The ratio of the user capacity to physical drive capacity.
*3  :  Rate when the rebuilding speed for the basic "RAID6 (D+P)" configuration is "1". The rate varies depending on the workload of the storage system and system environment.

Advanced Setting

Perform the advanced settings for RAID groups

Item Description Setting values

Stripe Depth

Stripe Depth should be selected only when advanced tuning needs to be performed for each RAID group. It is not necessary to change the default value for normal use.

The setting is not available when the RAID level is "RAID1". Available Stripe Depth value varies depending on the RAID level. Refer to Available Stripe Depth Value for details.

Note

  • Specifying a larger value for the Stripe Depth can reduce the number of drives to access. For RAID1+0, reducing the number of commands issued to drives improves the performance of access to the specified RAID group. For RAID5, however, specifying a larger value for the Stripe Depth might decrease the sequential write performance. In addition, several restrictions apply to a RAID group whose Stripe Depth has been changed and volumes created for such RAID group. Refer to Restrictions for Stripe Depth Modification for details.

64 KB (Default)

128 KB

256 KB

512 KB

1024 KB

Available Stripe Depth Value

The Stripe Depth values available for each RAID level are as follows:

RAID level Available Stripe Depth value
RAID1 -
RAID1+0, RAID0 64 KB, 128 KB, 256 KB, 512 KB, 1024 KB
RAID5 (2+1) - RAID5 (4+1) 64 KB, 128 KB, 256 KB, 512 KB
RAID5 (5+1) - RAID5 (8+1) 64 KB, 128 KB, 256 KB
RAID5 (9+1) - RAID5 (15+1) 64 KB, 128 KB
RAID5+0 64 KB
RAID6 64 KB
RAID6-FR 64 KB

Restrictions for Stripe Depth Modification

Note that the following restrictions apply to a RAID group whose Stripe Depth has been changed and volumes created for such RAID group.

  • The Stripe Depth of the RAID groups already created cannot be changed .

  • When selecting drives automatically to create a RAID group, the Stripe Depth cannot be changed.

  • The capacity cannot be expanded if the Stripe Depth of the RAID group has been changed (LDE is not available).

  • Encryption cannot be performed for volumes that are created in a RAID group whose Stripe Depth has been changed.

[Tabular] Tab

Click the [Tabular] tab.

Item Description

Enclosure

The enclosure where the drive is installed is displayed.

   CE: Controller Enclosure

   DE: Drive Enclosure

CE

CE#n

DE#n

Slot No.

The slot number of the enclosure where the drive is installed is displayed.

Type

Refer to Drive Type for details.

Capacity

The capacity of the drive is displayed.

Caution

  • The displayed drive capacity may differ from the product's actual capacity. For example, the drive capacity of a "1.92 TB SSD" is displayed as "2.00 TB".

Speed

The drive speed is displayed.

For SSD, NVMe SSD, SSD SED, or NVMe SSD SED, a "-" (hyphen) is displayed.

10000 rpm

7200 rpm

[Graphic] Tab

Click the [Graphic] tab to select drives from the drive installation image. The installation images of all the drives installed in the storage system are displayed. Checkboxes are displayed for unused drives.

There are conditions for the ETERNUS DX8100 S6/DX8900 S6 drive layout. Refer to Conditions for the ETERNUS DX8900 S6 Drive Layout for details. Note that these conditions are not applied to other models.

Item Description

DE selection list box

Select the DE group.

Options are displayed in the list box when at least one CE or DE in the DE group is installed in the storage system.

Refer to DE selection list box for details on the options and DE groups for each model.

DE

Only the CEs or the DEs in the selected DE group that are installed in the storage system are displayed.

CE

CE#n

DE#n

Checkbox to select drives

Select the checkbox for the drive that is to be used.

Checkboxes are displayed for unused drives. For 2.5" CEs or 2.5" DEs, drives are displayed from left to right in ascending order of the slot number. For 3.5" CEs or 3.5" DEs, drives are displayed from bottom left to top right in ascending order of the slot number.

Placing the mouse pointer on the icon displays the detailed information of the drive.

Conditions for the ETERNUS DX8900 S6 Drive Layout

The drive layout to configure RAID groups in the ETERNUS DX8900 S6 must satisfy the conditions described below.

RAID groups cannot be created if the required conditions are not satisfied.

For the ETERNUS DX8900 S6

RAID level Drive layout conditions
RAID1 Required

Allocate mirroring pair drives to different CEs and DEs.
Recommended

Allocate mirroring pair drives to DEs (*1) under different CEs when possible.

Allocate mirroring pair drives to different cascades (*2) when possible.
RAID1+0 Required

Allocate mirroring pair drives to different CEs and DEs.
Recommended

Allocate mirroring pair drives to DEs (*1) under different CEs when possible.

If drives are allocated in DEs under the same CE, allocate mirroring pair drives to different cascades (*2) when possible.
RAID5 Required

Allocate member drives to different CEs and DEs.
Recommended

Allocate member drives to DEs (*1) under different CEs when possible.

If drives are allocated in DEs under the same CE, allocate member drives to different cascades (*2) when possible.
RAID5+0 Required

Allocate two or less member drives to the same CE or DE.

Member drives in the same CE or DE must belong to different redundant groups.
Recommended

Allocate two or less member drives to DEs under the same CE when possible.

If drives are allocated in DEs under the same CE, allocate two or less member drives to DEs under the same CE in the same cascade (*2) when possible.

RAID6

RAID6-FR

 Required

Allocate two or less member drives to the same CE or DE.
Recommended

Allocate two or less member drives to DEs under the same CE when possible.

If drives are allocated in DEs under the same CE, allocate two or less member drives to DEs under the same CE in the same cascade (*2) when possible.
*1  :  DEs under different CEs have different numbers as the first digit of the DE number.
*2  : 

"Cascade" refers to DEs that are connected to one Backend cable (drive interface port).

DE#x1, DE#x2, and DE#x3 that are connected to CE#x/DA#0 Port#0 (x:0 - B)

DE#x4, DE#x5, DE#x6, and DE#x7 that are connected to CE#x/DA#0 Port#1 (x:0 - B)

DE#x8, DE#x9, DE#xA, and DE#xB that are connected to CE#x/DA#1 Port#0 (x:0 - B)

DE#xC, DE#xD, DE#xE, and DE#xF that are connected to CE#x/DA#1 Port#1 (x:0 - B)

(Example) DE#01, DE#02, and DE#03 that are connected to CE#0/DA#0 Port#0 are on the same cascade.

DE selection list box

Model Option DE group

ETERNUS DX600 S6

 DE#0x CE, DE#01 - DE#0A
DE#1x DE#10 - DE#1A
DE#2x DE#20 - DE#2A
DE#3x DE#30 - DE#3A

ETERNUS DX900 S6

 DE#0x

CE#0, DE#01 - DE#0F
DE#1x CE#1, DE#11 - DE#1F
DE#Cx DE#C0 - DE#CF
DE#Dx DE#D0 - DE#DF
DE#Ex DE#E0 - DE#EF
DE#Fx DE#F0 - DE#FF
ETERNUS DX8900 S6 DE#0x CE#0 (*1), DE#01 - DE#0F
DE#1x CE#1 (*1), DE#11 - DE#1F
DE#2x CE#2 (*1), DE#21 - DE#2F
DE#3x CE#3 (*1), DE#31 - DE#3F
DE#4x CE#4 (*1), DE#41 - DE#4F
DE#5x CE#5 (*1), DE#51 - DE#5F
DE#6x CE#6 (*1), DE#61 - DE#6F
DE#7x CE#7 (*1), DE#71 - DE#7F
DE#8x CE#8 (*1), DE#81 - DE#8F
DE#9x CE#9 (*1), DE#91 - DE#9F
DE#Ax CE#A (*1), DE#A1 - DE#AF
DE#Bx CE#B (*1), DE#B1 - DE#BF
*1  :  Only 2.5" drives can be installed.

Operating Procedures

Automatically Selecting Drives to Create RAID Groups

  1. Click [Create] in [Action].

  2. Select "Automatic" for "Create Mode".

  3. Specify the RAID group detailed information, and click the [Create] button.

    → A confirmation screen appears.

    Caution
    • An error screen appears in the following conditions:

      • The "Name" overlaps with an existing name (when one RAID group is created)

      • The "Name" does not satisfy the input conditions

      • RAID groups cannot be created by using the drives that are installed in the storage system

  4. Click the [OK] button.

    → RAID group creation starts.

  5. Click the [Done] button to return to the [RAID Group] screen.

Manually Selecting Drives to Create RAID Groups

  1. Click [Create] in [Action].

  2. Select "Manual" for "Create Mode".

  3. Specify the RAID group detailed information.

  4. Select drives using a list of the drives or the installation location image.

    Note

    • When the number of drives for each RAID level and the number of selected drives does not match, the [Create] button cannot be clicked.

  5. Click the [Create] button.

    → A confirmation screen appears.

    Caution
    • An error screen appears in the following conditions:

      • The "Name" overlaps with an existing RAID group name

      • The "Name" does not satisfy the input conditions

      • The drive layout does not satisfy the required conditions

        (Refer to Conditions for the ETERNUS DX8900 S6 Drive Layout for details.)

      • The specified Stripe Depth is not allowed for the RAID level

  6. Click the [OK] button.

    → RAID group creation starts.

  7. Click the [Done] button to return to the [RAID Group] screen.