Brocade Communications Systems FastIron SX 1600, Configuration Manual, Page: 252 / 593

FIGURE 25 Example OSPF network with four equal-cost paths
The device has four paths to R1:
• Router ->R3
• Router ->R4
• Router ->R5
• Router ->R6
Normally, the device will choose the path to the R1 with the lower metric. For example, if the metric for R3 is 1400 and the metric for R4
is 600, the device will always choose R4.
However, suppose the metric is the same for all four routers in this example. If the costs are the same, the router now has four equal-cost
paths to R1. To allow the router to load share among the equal cost routes, enable IP load sharing. The software supports four equal-cost
OSPF paths by default when you enable load sharing.
NOTE
The device is not source routing in these examples. The device is concerned only with the paths to the next-hop routers, not the
entire paths to the destination hosts.
OSPF load sharing is enabled by default when IP load sharing is enabled.
Configuring OSPF
FastIron Ethernet Switch Layer 3 Routing
252 53-1003627-04