OSPF area Connectivity

General
1

Is it possible in OSPF to have a link between 2 diff. route of 2 diff. area except area “0” ?

If, yes then how OSPF will work and what are the information they will share eachother and in which flow ?

2

Hi Mahesh,

Please make a topology and share it with us then will help you according to your own topology.

first of all you need to understand some basic rules.

  1. that you must have Area 0.
  2. why area 0 ? area 0 is contagious
  3. So you need ABR to convert Router LSA into Summary LSA.
  4. Remember ABR is any router that one interface is participating in Area 0 and any other area.

unless if we achieve that by virtual link, but you still need Area 0.

3

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You mean something like this mahesh ?

if your answer yes. then my answer is no.

you second question is how will you solve this right ?

  1. on R1 just configure a loopback and also put it it in Area 0.
  2. second option is on R0 or R2 configure Area 0 on one of the interface and make a OSPF virtual link.

Surely Atul Sir will cover this but not sure. if he doesnt I would gladly ask you to join his ENARSI batch.

cheers

4

mahesh you can use OSPF virtual link concept

5

In this, links between Area-1 & Area-3, Area-2 & Area-3. are possible in OSPF or not ?

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6

Yes its can be connected using OSPF virtual Links. Its a part of CCNP ENARSI.