Administrator Guide

• Non-Redundant: Uses RAID 0 in all classes, in all tiers. Data is striped but provides no redundancy. If one drive fails, all data is lost.

NOTE: Non-Redundant is not recommended because data is not protected against a drive failure. Do not use non-redundant

storage for a volume unless the data has been backed up elsewhere.

Redundancy levels per tier include single or dual redundant. The options may be restricted depending on the disk size.

• Single Redundant: Single-redundant tiers can contain any of the following types of RAID storage:

– RAID 10 (each drive is mirrored)

– RAID 5-5 (striped across 5 drives)

– RAID 5-9 (striped across 9 drives)

• Dual redundant: Dual redundant is the recommended redundancy level for all tiers. It is enforced for 3 TB HDDs and higher and for 18

TB SSDs and higher. Dual-redundant tiers can contain any of the following types of RAID storage:

– RAID 10 Dual-Mirror (data is written simultaneously to three separate drives)

– RAID 6-6 (4 data segments, 2 parity segments for each stripe)

– RAID 6-10 (8 data segments, 2 parity segments for each stripe.)

Redundancy Requirements

Drive size is used to determine the redundancy level to apply to a tier of drives. If any drive in a tier surpasses a threshold size, a specic

redundancy level can be applied to the tier containing that drive. If a redundancy level is required, the

Storage Center operating system sets

the level and it cannot be changed.

Table 2. HDD Redundancy Recommendations and Requirements

Disk Size Level of Redundancy Recommended or Enforced

Up to 3 TB Dual redundant is the recommended level

NOTE: Non-redundant storage is not an option for

SCv2000 Series Storage Centers.

3 TB and higher Dual redundant is required and enforced

Table 3. SSD Redundancy Recommendations and Requirements

Disk Size Level of Redundancy Recommended or Enforced

Up to 18 TB Dual redundant is the recommended level

NOTE: Non-redundant storage is not an option for

SCv2000 Series Storage Centers.

18 TB and higher Dual redundant is required and enforced

Disk Management

Storage Center manages both physical disks and the data movement within the virtual disk pool. Disks are organized physically, logically,

and virtually.

• Physically – Disks are grouped by the enclosure in which they reside, as shown in the Enclosures folder.

• Logically – Disks are grouped by class in disk folders. Storage Center enclosures may contain any combination of disk classes.

• Virtually – All disk space is allocated into tiers. The fastest disks reside in Tier 1 and slower drives with lower performance reside in Tier

3. Data that is accessed frequently remains in Tier 1, and data that has not been accessed for the last 12 progression cycles is gradually

migrated to Tiers 2 and 3. Data is promoted to a higher tier after three days of consistent activity. Disk tiering is shown when you select

a Storage Type.

For SC7020, SC5020, and SCv3000, Storage Center uses the Automatic Drive Placement function to manage drives automatically. When

conguring a storage system, Storage Center manages the disks into folders based on function of the disk. FIPS-certied Self-Encrypting

Storage Center Overview