Dell PowerConnect B-RX Configuration Manual page 745

FIGURE 102
If the DR goes off-line, the BDR automatically becomes the DR. The router with the next highest
priority becomes the new BDR. This process is shown in
NOTE
Priority is a configurable option at the interface level. You can use this parameter to help bias one
router as the DR.
FIGURE 103
If two neighbors share the same priority, the router with the highest router ID is designated as the
DR. The router with the next highest router ID is designated as the BDR.
BigIron RX Series Configuration Guide
53-1001986-01
Designated and backup router election
Designated Backup Router
priority 5
Router C
Backup designated router becomes designated router
Designated Backup Router
priority 5
Router C
Overview of OSPF (Open Shortest Path First)
priority 10
Router A
Designated Router
priority 20
Figure 103.
Designated Router
priority 10
Router A
priority 20
Router B
Router B
X
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