Qlogic SANbox2-8c Guía de instalación descargar pdf (Pagina 29)

3 – Planning

Multiple Chassis Fabrics

59042-01 A 3-3



3.2.2

Common Topologies

This section describes three commonly used topologies:

■ Cascade

■ Mesh

■ Multistage®

3.2.2.1

Cascade Topology

A cascade topology describes a fabric in which the switches are connected in a

line. If you connect the last switch back to the first switch, you create a

cascade-with-a-loop topology as shown in Figure 3-1. The loop reduces latency

because any switch can route traffic in the shortest direction to any switch in the

loop. The loop also provides failover should a switch fail.

The cascade fabric shown in Figure 3-1 has the following characteristics:

■ Each chassis link contributes up to 200 MB/s of bandwidth between chassis,

400 MB/s in full duplex. However, because of the structure of the cascade

topology, the bandwidth will be shared between devices on other chassis.

■ Latency between any two ports is no more than three chassis hops.

■ 24 Fibre Channel ports are available for devices.

Figure 3-1. Cascade-with-a-Loop Topology

1 2 ... 24 25 26 27 28 29 30 31 32 33 34 ... 161 162

Sin comentarios

Qlogic SANbox2-8c Guía de instalación Pagina 29