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Disk Array High Availability Features
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Disk Array High Availability Features
High availability systems are designed to provide uninterrupted operation should a
hardware failure occur. Disk arrays contribute to high availability by ensuring that user
data remains accessible even when a disk or other component within the Disk Array FC60
fails. Selecting the proper Fibre Channel topology and system configuration can protect
against the failure of any hardware component in the I/O path to the disk array by providing
an alternate path to all user data.
The Disk Array FC60 provides high availability in the following ways:
• Supported RAID levels 1, 0/1, 3, and 5 all use data redundancy to protect data when a disk
failure occurs. RAID 0 is supported but it does not offer data redundancy and should not
be used in high-availability environments.
• Global hot spare disks serve as automatic replacements for failed disks.
• Alternate hardware paths to user data protects against I/O path failures.
• Redundant, hot-swappable hardware components can be replaced without interrupting
disk array operation.
RAID Technology
RAID technology contributes to high availability through the use of data redundancy,
which ensures that data on the disk array remains available even if a disk or channel failure
occurs. RAID technology uses two techniques to achieve data redundancy: mirroring and
parity. A third characteristic of RAID technology, data striping, enhances I/O performance.
Disk Mirroring
Disk mirroring achieves data redundancy by maintaining a duplicate copy of all data. Disks
are organized into pairs: one disk serves as the data disk, the other as the mirror which
contains an exact image of its data. If either disk in the pair fails or becomes inaccessible,
the remaining disk provides uninterrupted access to the data.
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 ...