Q-Logic 5800V Manuel D’Utilisation
2–Planning
Multiple Chassis Fabrics
59265-02 B
2-11
Cascade Topology
A cascade topology describes a fabric in which the switches are connected in
series. If you connect the last switch back to the first switch, you create a
cascade-with-a-loop topology as shown in
series. If you connect the last switch back to the first switch, you create a
cascade-with-a-loop topology as shown in
. 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 if a switch fails.
loop. The loop also provides failover if a switch fails.
Using 24-port QLogic 5800V Series switches, the cascade fabric shown in
has the following characteristics:
Each chassis link contributes up to 850MB of bandwidth between chassis,
1700MB in full duplex. However, because of the sequential structure, that
bandwidth is shared by traffic between devices on other chassis.
1700MB in full duplex. However, because of the sequential structure, that
bandwidth is shared by traffic between devices on other chassis.
Latency between any two ports is no more than two chassis hops.
Sixty-four Fibre Channel SFP ports are available for devices.
Figure 2-6. Cascade-with-a-Loop Topology