Hot Downloads



The forum is in read only mode.
Welcome, Guest
Username: Password: Remember me
  • Page:
  • 1

TOPIC: OSPF DR and BDR election

OSPF DR and BDR election 12 years 3 months ago #18887

Hi, I have a doubt related to the OSPF DR and the BDR election.

If Router A is a DR and Router B is BDR. Now router A fails and B becomes the DR. What will happen when router A comes up. Will there be a re-election ??

Re: OSPF DR and BDR election 11 years 11 months ago #21107

  • krik
  • krik's Avatar
  • Offline
  • Frequent Member
  • Frequent Member
  • Posts: 69
  • Thank you received: 0
When an OSPF router becomes active and discovers its neighbors, it checks for an active DR and BDR. If a DR and BDR exist, the router accept them. If there is no BDR, an election is held in which the router with the highest priority becomes the BDR. If there is no active DR, the BDR is promoted to DR and a new election is held for the BDR.

It should be noted taht the priority can influence an election, but will not override an active DR or BDR. If there are already DR and BDR on the LAN, they will remain DR and BDR until a failure.
Christophe Lemaire

Re: OSPF DR and BDR election 10 years 8 months ago #26690

untill OSPF reload it wont take any decision on router A as a DR or BDR .

DR BDR election 10 years 4 months ago #27938

Pls tell me , In a DR , BDR election , Is it the DR or BDR getting elected first?

DR/BDR 9 years 3 months ago #33050

Hi jack,

If I understood your question properly, you asking which one is elected first, DR or BDR?

for that:

The DR is the first to be elected, and then the same process will repeat again for electing the BDR.
Kenneth Chong
  • Page:
  • 1
Time to create page: 0.113 seconds


Cisco Routers

  • SSL WebVPN
  • Securing Routers
  • Policy Based Routing
  • Router on-a-Stick

VPN Security

  • Understand DMVPN
  • GRE/IPSec Configuration
  • Site-to-Site IPSec VPN
  • IPSec Modes

Cisco Help

  • VPN Client Windows 8
  • VPN Client Windows 7
  • CCP Display Problem
  • Cisco Support App.

Windows 2012

  • New Features
  • Licensing
  • Hyper-V / VDI
  • Install Hyper-V


  • File Permissions
  • Webmin
  • Groups - Users
  • Samba Setup