EMC VMAX 100K, Product Manual

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Pre-configuration for FAST
VMAX3 arrays are custom-built and pre-configured with array-based software
applications, including a factory pre-configuration for FAST that includes:
l
Data devices (TDAT) — an internal device that provides physical storage used by
thin devices.
l
Data pool — a collection of data devices of identical emulation and protection
type, all of which reside on disks of the same technology type and speed. The
disks in a data pool are from the same disk group.
l
Disk group— a collection of physical drives within the array that share the same
performance characteristics, which are determined by rotational speed (10K and
7.2K), technology (SAS, flash SAS), and capacity.
RAID protection options are configured at the disk group level. EMC strongly
recommends that you use one or more of the RAID data protection schemes for all
data devices.
Table 36 RAID options
RAID
a
Provides the following Configuration
considerations
RAID 1 The highest level of
performance for all mission-
critical and business-critical
applications. Maintains a
duplicate copy of a device on
two drives.
If a drive in the mirrored pair
fails, the array automatically
uses the mirrored partner
without interruption of data
availability.
n
Withstands failure of a
single drive within the
mirrored pair.
n
A drive rebuild is a simple
copy from the remaining
drive to the replaced
drive.
n
The number of required
drives is twice the amount
required to store data
(usable storage capacity
of a mirrored system is
50%).
RAID 5 Distributed parity and striped
data across all drives in the
RAID group. Options include:
n
RAID 5 (3 + 1) — Consists
of four drives with parity
and data striped across
each device.
n
RAID 5 (7 + 1) — Consists
of eight drives with data
and parity striped across
each device.
n
RAID 5 (3 + 1) provides
75% data storage
capacity.
n
RAID 5 (7 + 1) provides
87.5% data storage
capacity.
n
Withstands failure of a
single drive within the
RAID 5 group.
RAID 6 Striped drives with double
distributed parity (horizontal
and diagonal). The highest
level of availability options
include:
n
RAID 6 (6 + 2) provides
75% data storage
capacity.
Storage Tiering
Pre-configuration for FAST 85