Users Guide

PowerVault™ 50F Topologies: Dell™ PowerVault™ 50F 8-Port Fibre Channel Switch Installation and Troubleshooting Guide
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installation. Functionally, the switch becomes a Fabric with every device connected to every other device by
the Fabric.
Each connection is full duplex with transmissions up to 1 Gbps bandwidth simultaneously, in both directions,
between the Fabric and Fabric-connected devices.
Two-Switch Sample Topology
The two-switch topology increases the number of connectivities and aggregate Fabric bandwidth, as shown
schematically in Figure 2-5. The switches are shown physically connected although the connections are
transparent in the Fabric. Functionally, the devices appear to be connected together directly.
Figure 2-5. Fabric Topology Sample With Three Connections Between Two Switches
When a Fabric is initiated, or when a new switch is added to the Fabric, the switches determine a least-cost
path for each destination switch. This is done dynamically each time the Fabric configuration changes and
the results are stored in the switch's internal routing tables.
NOTE: After a path has been determined, it is not rerouted, even though traffic volume may change over time, for each
path to maintain in-order delivery. If the link fails, the path is rerouted.
Increasing Local Bandwidth within the Fabric
In Figure 2-5, three connections are shown between Switch A and Switch B. This gives an aggregate
bandwidth of six Gbps - three 1-Gbps, full-duplex connections. Increasing bandwidth between switches is
done by adding additional connections between the switches.
In addition to the bandwidth, redundant connections between the switches in Figure 2-5 provide a high-
bandwidth, fault-tolerant Fabric.
Four-Switch Sample Topology