I might need to clarify: What we are talking about is, once the devices begin an election, how long do they wait before they say "OK, no new candidates... let's vote"? The questions that you proposed are not part of this scenario. They are, however, perfect examples of what would make R3 "too late" for the election process.
Let's also a assume a perfect understanding of the protocol from a Cisco perspective as presented by Doyles book. I've not heard of him or Cisco.com mentioning this. I would assume that it's some integral factor of the hello time, but that's a complete guess. On Tue, Nov 23, 2010 at 7:24 PM, Jason Maynard <[email protected]>wrote: > Well that depends > > > > How long does the device take to boot up compared to other devices > > When is the device ready to participate in the OSPF election process > (running more services on a device may take it longer to start participating > compared to a router with less services) > > > > DR and BDR election is done via the Hello protocol – > > > > OSPF Network Type | Hello | DR/BDR | > _________________________________________ > Broadcast | 10sec | Elects DR/BDR| > _________________________________________ > NonBroadcast | 30sec | Elects DR/BDR| > _________________________________________ > P2MP | 30sec | No DR/BDR | > _________________________________________ > P2MP NonBroadcast | 30sec | No DR/BDR | > _________________________________________ > P2P | 10sec | No DR/BDR | > > > > If you want to control which devices become the DR/BDR you can use “*ip > ospf priority” and set all devices that you do not want to be DR/BDR to “0” > *** > > > > Not sure exactly how may hellos before the DR/BDR election takes place, > perhaps I will lab it up to see - > > > > HTH > > > > > > > > > > *From:* [email protected] [mailto: > [email protected]] *On Behalf Of *David Betz > *Sent:* November-23-10 7:32 PM > *To:* [email protected] > *Subject:* [OSL | CCIE_RS] OSPF Election Time > > > > I've not been able to figure this out nor can I find any documentation for > this: how long does OSPF wait for others to cast their vote before doing the > DR/BDR election? > > > > If R1, R2, and R3 come online with 10.1.1.X/25 (X=RX) ip addresses, and R1 > and R2 see each other's messages, they will start an election. If R3 is > there, it wins... if it's too late, R2 wins. > > > > When is "too late"? >
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