OSPF: External routes (ABR vs ASBR)

[Ruben Laban]

On 10/9/2012 5:07 PM, Ondrej Zajicek wrote:
> On Tue, Oct 09, 2012 at 03:51:46PM +0200, Ruben Laban wrote:
>> Hi Ondrej,
>>
>> On 10/9/2012 3:04 PM, Ondrej Zajicek wrote:
>>> On Tue, Oct 09, 2012 at 11:16:24AM +0200, Ruben Laban wrote:
>>>> Hi list,
>>>>
>>>> I'm trying to figure out how bird distinguishes between imported routes
>>>> that are shown as "external" route directly under the router's id (in
>>>> "show ospf state") and those listed under the "other ASBRs" header. I
>>>> have different boxes showing different behavior. I just can't seem to
>>>> pinpoint the reason for a route show up under the "other ASBRs" header.
>>>
>>> If current router does not have router LSA for that ASBR then its routes
>>> are listed under "other ASBRs" header. These are usually ASBRs from
>>> non-adjacent areas.
>>
>> I'm afraid my lack of in-depth OSPF terminology is failing me here a
>> bit, as I can't make much from what you just said.
>>
>> The routers listed as "other ASBRs" are listed under "area 0.0.0.0" as
>> well. With stubnets listed in area 0.0.0.0, and externals listed as
>> under other ASBRs. This happens for 2 (unrelated) routers in my
>> networks. I have several other routers in my network where the stubnets
>> and externals are listed just fine directly in the "area 0.0.0.0" block.
>
> If you have just one area (0.0.0.0), then you shouldn't get
> "other ASBRs". Or perhaps only in the case that given routers
> are unreachable or when LSA databases are not properly synchronized.
> Could you send me the output of:
>
> show ospf state
> show ospf state all
> show ospf lsadb
> show ospf neighbors
>
> on 'strange' and normal node?
>

To summarize my discussion with Ondrej off-list: it turned out to a 
display bug in "show ospf state".

Regards,
Ruben Laban