Ospf totally stub

[ShaunEini3096]

Thanks 

Hi experts 

i configured In my  small network two totally stub areas . I can ping from host in on area to all the switches and routers in the network but I can’t ping to one loopback that in one of the totally stub areas . Can you please help me what it can be ? Maybe something that I configure wrong? 

Thanks 

[Giuseppe Larosa]

Hello Shaun,

you need to look at the OSPF database to verify if a type 3 summary LSA exists for the loopback address.

If for example the loopback address is 10.10.11.22/32 is in totally stub area 2.

check on the ABR node between totally stub area1 and area 0 if the ABR sees an entry

with

show ip ospf database summary 10.10.11.22

if an entry does not exist in this ABR (0, totally-stub-area1) you have a problem.

Remember that you cannot use redistribute  command within a totally stub area router even redistributed connected is not allowed (you can configure it but it is not effective)

on the remote router in totally-stub-area2 you need the following config

router ospf 1

area 5 stub

network 10.10.11.22 0.0.0.0 area 5

+

additional network commands in appropriate area in this example I have used 5 as totally-stub-area 2.

What is more important is the design of your multi area OSPF domain all areas need to be connected to area 0.

So a correct design would be

R1----- R2  ----- R3 ------- R4 ------ R5

area 4      !      area 0                  !    area 5

totally stub                                      totally stub

If area 5 is not connected to area 0 routing does not work

The following design is not supported

R1----- R2  ----- R3 ------- R4 ------ R5

area 4      !      area 0 !   area 2          !    area 5

totally stub                                      totally stub

Hope to help

Giuseppe

[ShaunEini3096]

All the totally stub areas are connecting to area 0 and I hav e ping between them. Also when I ping fro one  totally stub area to other it’s working but not the Opposite side it doesn’t work I have an request timed out

thank you very match for your  pension 

[balaji.bandi]

Can you show us some examples and output of the same out for the ospf Database for that network.

[Richard Burts]

We do not have enough information yet to be able to identify the problem. As a start will you identify the device that has the loopback that you can not ping and post the output of show run interface loopback from that device? Also would you post the output of show ip interface brief and of show ip ospf interface from that device? And can you post the configuration of OSPF on that device?

HTH

Rick

[paul driver]

Hello

---

@ShaunEini3096 wrote:

Thanks 

Hi experts 

i configured In my  small network two totally stub areas . I can ping from host in on area to all the switches and routers in the network but I can’t ping to one loopback that in one of the totally stub areas .

---

Is that loopback advertised in ospf?

show ip ospf interface loopback x

[Richard Burts]

Another thing that would be quite helpful would be for the original poster to post the output of traceroute from the device that is attempting the ping that does not work. This would show us whether the problem is in the first hop or whether the traffic gets part way through the network (perhaps to area 0) and then has a problem.

HTH

Rick