ospf DR and BDR

[fsoffia]

hallo, I have some questions about ospf not cleared by other docs.

In a LAN segment, inside an ospf area 0, we have a DR and BDR.

1) If the DR goes down the BDR become DR ?

2) If the DR return back up it will be always the DR ?

3) if DR goes down and BDR become DR, a new BDR will be elected ?

4) the routers that aren't DR or BDR have in the adjacensy database only DR and BDR, or all the other routers in the lan ?

best regards

francesco

[mahmoodmkl]

Hi

yes u r right when the DR goes down BDR will become DR and new BDR is elected.

not sure of u r 2&3 question.

Yes all the routers in a broadcast multiaccess network all the routers are going to have adjacency with DR and BDR instead of having adjacency with evry router.this is to prevent flooding of LSA's

Thanks

Mahmood

[Harold Ritter]

1) BDR becomes DR indeed.

2) current DR remains DR for sake of stability.

3) A new BDR is indeed elected

4) correct

Hope this helps,

[rajeshk200_2]

Hi,

1&3. yes BDR will become DR and new BDR will be elected.

2. when DR returns active current DR still remains as DR.

4. Non DR/BDR will have adjacency with DR/BDR in that lan segment(broadcast domain)

HTH

Regards,

Rajesh