HP Surestore 64 FW 05.01.00 and SW 07.01.00 HP StorageWorks SAN High Availabil - Page 106

Redundant fabrics

Page 106 highlights

Planning Considerations for Fibre Channel Topologies Figure 45 illustrates simple redundant fabrics. Fabric "A" and fabric "B" are symmetrical, each containing one core director and four edge switches. All servers and storage devices are connected to both fabrics. 10/100 RST TM PWR ERR 10/100 RST TM PWR ERR Fabric "A" TM 10/100 RST TM PWR ERR 10/100 RST TM PWR ERR Fabric "B" TM 10/100 RST TM PWR ERR 10/100 RST TM PWR ERR 10/100 RST TM PWR ERR 10/100 RST TM PWR ERR Interswitch Link Fabric Connection Figure 45: Redundant fabrics Some dual-attached devices support active-active paths, while others support only active-passive paths. Active-active devices use either output path equally, and thus use both fabrics and double the device bandwidth. Active-passive devices use the passive path only when the active path fails. When deploying redundant fabrics, it is not required that the fabrics be symmetrical. As an example, single-attached devices, such as tape drives and noncritical servers and storage, can be logically grouped and attached to one of the fabrics. 106 SAN High Availability Planning Guide

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Planning Considerations for Fibre Channel Topologies
106
SAN High Availability Planning Guide
Figure 45
illustrates simple redundant fabrics. Fabric “A” and fabric “B” are
symmetrical, each containing one core director and four edge switches. All
servers and storage devices are connected to both fabrics.
Figure 45:
Redundant fabrics
Some dual-attached devices support active-active paths, while others support only
active-passive paths. Active-active devices use either output path equally, and thus
use both fabrics and double the device bandwidth. Active-passive devices use the
passive path only when the active path fails.
When deploying redundant fabrics, it is not required that the fabrics be
symmetrical. As an example, single-attached devices, such as tape drives and
noncritical servers and storage, can be logically grouped and attached to one of the
fabrics.
Interswitch Link
Fabric Connection
Fabric
“A”
Fabric
“B”