FW 05.01.00 and SW 07.01.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DC-TE, June 2003)

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
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