Sina Mirtorabi wrote:

> Acee,
>
> Acee Lindem wrote:
>
>
>>Nehal Bhau wrote:
>>
>>
>>>Hi folks,
>>>
>>>Consider the following simple network topology.
>>>
>>> N1
>>>N2
>>> R1--------------R2--------------|
>>> Area 0
>>>Area 1
>>>
>>>
>>>
>>>R1 is an ASBR configure to advertise a route (AS External LSA)
>>>to some network N3 with next-hop set to a non-OSPF router on network
>>>N2.
>>>
>>>The question is, should R1 set the forwarding address to be the
>>>address
>>>on network N2 ? It seems R1 will have an inter-area route to network
>>>N2.
>>>
>>If R1 is attached to Area 1, it is an intra-area route.
>>
>>
>>>So, it should set the forwarding address (which is an address on N2).
>>>
>>>Is that correct ?
>>>
>>If R1 has an OSPF intra-area or inter-area route to N2, then it should
>>set the forwarding address.
>>
>>
>
> the ASBR that is originating type 5 LSA in charge of setting the forwarding
> address in our case R1, is directly connected to the nexthop ( forwarding
> address ) so it can never have an Inter area route to this forwarding
> address.

Sina,

If R1 has OSPF configured on it's interface connecting to N2, it will have
an intra-area route.

> however once the forwarding address is set for type 5 other route must have
> an intra or inter area route to the forwarding address.

>
> Nehal
>
> other condition to set the forwarding address ( although it is not
> explicitly mentioned ) is that the interface to the next hop should be
> Multi-access since setting it on p2p is equivalent to setting it to zero (
> we assume that OSPF is enabled on the interface )
>
> Sina
>
>
>
>>>Thanks,
>>>
>>>-Nehal
>>>
>>>
>>>
>

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