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Could an OSPF router be configured so that it can only see its own area LSAs and does not accept LSAs from other areas? (For example, if it is in area 2, its routing table just shows routes in area 2, disconnected from the rest of the areas)

Perhaps by setting a stub area? Or by doing something tricky?

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    You could just not have it be neighbors with the ABR
    – Ron Trunk
    May 31, 2022 at 2:00
  • the whole point of a routing protocol is to exchange routes. What is the point if you block half the process? remember that most of network communication is bi-directional and if you router doesn't see the routes of the rest of the network it effectively cannot communicate with it (unless you have routes setup another way of course) and you may as well not use OSPF at all.
    – JFL
    May 31, 2022 at 8:01
  • I want this router to see the ABR's subnets which are located in the same area. But no visibility of other areas to this router...Any straightforward way to prevent this kind of neighborship? @RonTrunk
    – A.A
    May 31, 2022 at 8:11
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    On the ABR, create two OSPF processes -- one for area 2 and one for area 0. Use authentication to control which process get which neighbor. No redistribution between them.
    – Ron Trunk
    May 31, 2022 at 12:22
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    Do you want/need a default route? If so, what you're describing can be accomplished by configuring the area as a Totally Stub Area.
    – user83861
    May 31, 2022 at 13:54

1 Answer 1

Reset to default
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In most OSPF implementation you can filter routes advertised and received with route-map.

So one option would be to assign a route map that allows nothing on the received-routes.

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  • Unfortunately, It's not possible to filter routes in the ingress direction here. I don't know what to do...
    – A.A
    Jun 6, 2022 at 6:50

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