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
97SAN High Availability Planning Guide
Planning a Fibre Channel Fabric Topology
To be effective, the fabric topology design must:
■ Solve the customer’s business problem and provide the required level of
performance.
■ Meet the customer’s requirements for high availability.
■ Be scalable to meet future requirements.
Fabric Performance
During the design phase of a Fibre Channel fabric, performance requirements of
the fabric and of component directors, switches, and devices must be identified
and incorporated. An effective fabric design can accommodate changes to
performance requirements, and incorporate additional directors, switches, devices,
ISLs, and higher speed links with minimal impact to fabric operation.
Performance factors that affect fabric design include:
■ Application input/output (I/O) requirements, both in Gbps and I/Os per
second (IOPS).
■ Storage port fan-out.
■ Hardware limits, including the maximum directors and switches per fabric,
maximum number of ISLs per director or switch, and maximum hops between
devices. For additional information, refer to “Fabric Topology Limits” on
page 79.
■ Software limits, including the maximum number of fabric elements managed
by the HAFM application, and the maximum number of zones and zone
members. For additional information, refer to “Product Software” on page 47
and “Configuring Zones” on page 133.