
50
Disk Array High Availability Features
using a 5-disk RAID 5 LUN, a stripe segment size of 32 blocks (16
K
B) would ensure that an
entire I/O would fit on a single stripe (16
K
B on each of the four data disks).
The total stripe size is the number of disks in a LUN multiplied by the stripe segment size.
For example, if the stripe segment size is 32 blocks and the LUN comprises five disks, the
stripe size is 32 X 5, or 160 blocks (81,920 bytes).
RAID Levels
RAID technology uses a number of different techniques for storing data and maintaining
data redundancy. These industry-standard RAID levels define the method used for
distributing data on the disks in a LUN. LUNs that use different RAID levels can be created
on the same disk array.
The Disk Array FC60 supports the following RAID levels:
•
RAID 0
•
RAID 1
•
RAID 0/1
•
RAID 3 (Windows NT and Windows 2000 only)
•
RAID 5
RAID 0
C
AUTION
RAID 0 does not provide data redundancy. It should only be used in
situations where high performance is more important than data protection.
The failure of any disk within a RAID 0 LUN will cause the loss of all data on
the LUN.. RAID 0 should only be used for non-critical data that could be lost
in the event of a hardware failure.
RAID 0 uses disk striping to achieve high performance. Data is striped across all disk in the
LUN. The ability to access all disks in the LUN simultaneously provides a high I/O rate. A
RAID 0 group configuration for a logical disk unit offers fast access, but without the high
availability offered by the other RAID levels.
Unlike other RAID levels, RAID 0 does not provide data redundancy, error recovery, or
other high availability features. Consequently it should not be used in environments where
high-availability is critical. All data on a RAID 0 LUN is lost if a single disk within the LUN
Summary of Contents for Surestore Disk Array 12h - And FC60
Page 16: ...16 ...
Page 36: ...36 Array Controller Enclosure Components Figure 9 Controller Enclosure Front View ...
Page 41: ...Array Controller Enclosure Components 41 Product Description Figure 13 Controller Fan Module ...
Page 44: ...44 Array Controller Enclosure Components Figure 15 Power Supply Fan Module ...
Page 68: ...68 Capacity Management Features ...
Page 117: ...Topologies for HP UX 117 Topology and Array Planning Figure 39 High Availability Topology ...
Page 122: ...122 Topologies for HP UX Figure 40 High Availability Distance and Capacity Topology ...
Page 126: ...126 Topologies for HP UX Figure 41 Campus Topology ...
Page 130: ...130 Topologies for HP UX Figure 43 Four Hosts Connected to Cascaded Switches ...
Page 142: ...142 Topologies for Windows NT and Windows 2000 ...
Page 158: ...158 Installing the Disk Array FC60 Figure 54 Enclosure EIA Positions for System E Racks ...
Page 161: ...Installing the Disk Enclosures 161 Installation Figure 56 Disk Enclosure Contents ...
Page 172: ...172 Installing the Controller Figure 62 Controller Enclosure Package Contents ...
Page 174: ...174 Installing the Controller Figure 63 Mounting the Controller Enclosure ...
Page 234: ...234 Adding Disk Enclosures to Increase Capacity ...
Page 274: ...274 Managing the Disk Array Using SAM Unassigned disks selected as hot spares ...
Page 345: ...HP UX Diagnostic Tools 345 5 HP UX DIAGNOSTIC TOOLS Overview 346 Support Tools Manager 347 ...
Page 350: ...350 Support Tools Manager Figure 90 mstm Interface Main Window ...
Page 358: ...358 Support Tools Manager ...
Page 440: ...440 FCC Statements USA Only ...
Page 466: ...466 Index ...