Administrator Guide

Switches
Switches provide robust connectivity to servers, allowing for the use of multiple controllers and redundant transport paths. Cabling
between controller I/O cards, switches, and servers is referred to as front-end connectivity.
Enclosures
Enclosures house and control drives that provide storage. Enclosures are connected directly to controller I/O cards. These connections are
referred to as back-end connectivity.
Fibre Channel Switched Bunch of Disks (SBOD) and Serial Advanced Technology Attachment (SATA) enclosures are supported for existing
Storage Centers and for controller migrations only.
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
Drives (SEDs) are managed into a separate folder than other disks. When Storage Center detects new disks, it manages the disk into the
appropriate folder.
In Storage Center version 7.3 and later, the Automatic Drive Placement function can be turned on or o for all Storage Centers (except
SCv2000 series) using the Storage Center Storage settings. See below for SCv2000 series disk management.
Disk Management on SCv2000 Series Controllers
Storage Centers with SCv2000 series controllers manage disks automatically, limiting the disk management options. After adding disks,
Storage Center recognizes the new disks, creates a new disk folder if necessary, then manages the disks in the disk folder. If a disk is
intentionally down for testing purposes, then is deleted, you can restore the disk to manage the disk again in a disk folder.
The following disk management options are not available with SCv2000 series controllers:
• Creating disk folders
• Adding disks to disk folders
• Managing disk spares
Disk Folders
A disk folder contains both managed drives and spare disk space. Managed drives are used for data storage. Spare disk space is held in
reserve to automatically replace a drive if a drive fails. By default, the Assigned disk folder is the parent disk folder for all drives. Drives are
further grouped by class in subordinate folders.
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Storage Center Overview