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 SCv3000, SC5020, and SC7020 storage systems, Storage Center uses the Automatic Drive Placement function to manage
drives automatically. When configuring a storage system, Storage Center manages the disks into folders based on function
of the disk. FIPS-certified 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 off for all Storage Centers
(except SCv2000 series storage systems) using the Storage Center Storage settings.
Disk Management on SCv2000 series Storage Systems
Storage Centers with SCv2000 series storage systems 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 for SCv2000 series storage systems:
● 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.
Disk Classes
Disks are classified based on their performance characteristics. Each class is shown in a separate folder within the Assigned
disk folder.
● Hard Disk Drives (HDDs) – For HDDs, the disk classification describes its spindle speed and can be any of three disk types.
Storage Center Overview
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