Dell Force10 S4820T S4820T Configuration Guide - Page 694

www.dell.com | support.dell.com Figure 33-3. Priority and Costs Example Router 2 Priority 180 Cost 50 Router 3 Priority 100 Cost 25 Router 1 Priority 200 Cost 21 Router 4 Priority 150 Cost 20 Router 1 selected by the system as DR. Router 2 selected by the system as BDR. If R1 fails, the system subtracts 21 fromR1 s priority number. R1 s new pirority is 179. R2 as both the selected BDR and the now-highest priority, becomes the DR. If R3 fails, the system subtracts 50 fromits priority. R2 s new priority is130. R4 is now the highest priority and becomes the DR. Implementing OSPF with FTOS FTOS supports up to 10,000 OSPF routes. Within that 10,000 up to 8,000 routes can be designated as external and up to 2,000 designated as inter/intra area routes. FTOS version 7.8.1.0 and later support multiple OSPF processes (OSPF MP). The Z-Series supports up to 3 OSPF processes simultaneously. The S-Series supports up to 16 processes simultaneously. FTOS supports Stub areas, Totally Stub (No Summary) and Not So Stubby Areas (NSSAs) and supports the following LSAs, as discussed earlier in this document. • Router (type 1) • Network (type 2) • Network Summary (type 3) • AS Boundary (type 4) • AS External (type 5) 694 | Open Shortest Path First (OSPFv2)