It reads placing interface into DR & BDR fields if the router's priority is greater than 0, it can
1) claim that it is a DR/BDR (if it was elected earlier) Or 2) not claim and start listening to other routers hellos; then if no one claims to be DR/BDR, the router will take part in election. Here's a packet capture showing the fields http://ipcisco.com/wp-content/uploads/OSPF/A5_OSPF_hello.JPG -- BR Tony > On 21 Feb 2014, at 00:19, vishal bhugra <[email protected]> wrote: > > Hello Tony > > Thanks for your reply, > > I am not sure if my question is clear. > > If I rephrase my question - Why do a router will put his router ID in BDR > field and not the DR. or why do a router wants himself to be elected as BDR > and not the DR. > > > As mentioned in TCP-IP (Jeff Doyle) Part 1 > <image.png> > > >> On Thu, Feb 20, 2014 at 3:42 PM, Tony Singh <[email protected]> wrote: >> >> That's all to do with the hello from x being received first who at that >> point in time had the highest router-id at the time of the multi-access >> election and declared himself as the DR (default priority is 1 for all peers) >> >> OSPF DR/BDR elections are not pre-emptive >> >> debug ip ospf adjacency will show you what happens when >> >> If you had the above scenario then reset the current DR's process (lower >> router-id) to enable the highest router-id OSPF router take the DR role >> >> -- >> BR >> >> Tony >> >> >> >> > On 20 Feb 2014, at 23:28, vishal bhugra <[email protected]> wrote: >> > >> > Hello Experts >> > >> > While going through the DR and BDR election process. I gone through a line >> > wherein during the process of election the router will segregate the list >> > of routers who have mentioned themselves as BDR and those who have >> > mentioned themselves as DR. >> > >> > After segregation out of the list of BDR, the elected BDR will be with the >> > highest priority and if not then highest Router ID. >> > >> > Now my question is .. Why would a router will opt himself for BDR and not >> > for DR. Or we can say how a router will come to conclusion that it has to >> > go for be a BDR not the DR. >> > >> > -- >> > Thanks®ards >> > >> > Vishal >> > >> > Best way to predict the future ..... is to create it >> > >> > >> > Blogs and organic groups at http://www.ccie.net >> > >> > _______________________________________________________________________ >> > Subscription information may be found at: >> > http://www.groupstudy.com/list/CCIELab.html >> > >> > >> > >> > >> > >> > >> > > > > > -- > Thanks®ards > > Vishal > +91 8587900305 > > Best way to predict the future ..... is to create it _______________________________________________ Free CCIE R&S, Collaboration, Data Center, Wireless & Security Videos :: iPexpert on YouTube: www.youtube.com/ipexpertinc
