What is ospf dr bdr?


Explain dr bdr in OSPF.

How and why DR Bdr election happens.

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Dr-designated router
Bdr-backup designated router
To send routing information to a DR or BDR the multicast address is used DR send routing update to the multicast address of if DR fails BDR take over its role redistributing routing information.
DR or BDR election of highest ospf priority or highest ip address DR by default all router have a priority of 1



to avoid LSA flading we are using DR BDR process
multicast add DR 224.00.5

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First of all , DR/BDR election only happens in multi Access network.
Second, to avoid type1 LSA flooding in MA network.
Third, DR/BDR generate type 2 LSA.
Fourth, DR/BDR in full state rest other routers in 2-way state.
Fifth, DR/BDR use multi cast address

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to avoid lsa floading in ospf we are using ospf dr bdr