Administrator Guide

Router Priority and Cost
Router priority and cost is the method the system uses to “rate” the routers.
For example, if not assigned, the system selects the router with the highest priority as the DR. The second
highest priority is the BDR.
• Priority is a numbered rating 0 to 255. The higher the number, the higher the priority.
• Cost is a numbered rating 1 to 65535. The higher the number, the greater the cost. The cost assigned
reflects the cost should the router fail. When a router fails and the cost is assessed, a new priority
number results.
Figure 85. Priority and Cost Examples
OSPF with Dell Networking OS
Dell Networking OS supports up to 10,000 OSPF routes for OSPFv2. Within that 10,000 routes, you can
designate up to 8,000 routes as external and up to 2,000 as inter/intra area routes.
Dell Networking OS supports multiple OSPF processes (OSPF MP) on OSPFv2 only. The Z9000 platform
supports 32 OSPF processes simultaneously.
On OSPFv3, Dell Networking OS supports only one process at a time for all platforms.
OSPFv2 and OSPFv3 can coexist but you must configure them individually.
540
Open Shortest Path First (OSPFv2 and OSPFv3)