Problem with routing filters

RouterOS Forwarding Protocols
1

I think this is trivial, but it isnt working on my RB433GL or I am doing something wrong…consider this network:

                                                                               _______________
                                             _________(e.f.g.h/29)_|                        |____________(other networks)
                                             |                                 |______________|
                                      ____|______                           some ospf router1
     (a.b.c.d/24)          ____| RB433GL |
                                      |_________|               
                                             |                                  ______________
                                             |_________(o.p.q.r/29)_|                        |____________(other networks)
                                                                               |______________|
                                                                                     some ospf router2

My RB433GL is using OSPF as routing protocol…what I want is that my router advertise only a.b.c.d/24 prefix (sunbet) to routers router1 and router2, and nothing else…and to recieve all advertisment from this routers…well this implies that it would be natural to use routing filters…here is mine:

/ip routing filter add chain=omer prefix=a.b.c.d/24 action=accept
/ip routing filter add chain=omer action=discard

And this filter I added on /routing ospf instances as filter out…and this is not working…what is wrong? is there another way to achive this goal?

Sorry for bad network diagram, I was in hurry…

Thank you

2

I tried something similar once and ended up with one sentence but with “invert-match” and action “discard” or “reject”

Sorry, but i don´t seem to find back to this example code so give it a go.

3

I found something on this link: http://wiki.mikrotik.com/wiki/Manual:Routing/Routing_filters

There is a note:

Note that internal RIP filtering is done using prefix lists [and internal (intra-area) OSPF filtering is not supported yet]

So intra-area ospf routes cannot be filtered?..Is this correct?

4

You can filter only external OSPF routes.

5

Since all my routes are internal (all ospf routers are in single area) I cannot use route filtering…is there any solution to my problem?

Thank you

6

Why do you want to filter intra-area routes?

7

Ok in here is clear diagram (or not?)…links between my router RB433GL and Router1 and Router2 are wireless with low bandwidth…when my router advertise routes to other two routers, they begin to send traffic, ono to another over my router, across wireless links, and thats a bottleneck…there is a lot of traffic between these two routers…so i want stop advertise routes to these two routers except my subnet a.b.c.d/24…in this scenario Router1 and Router2 would communicate over optical network…
Diagram1.png

8

Set on Router1 and router2 lower OSPF distance on optical link, then it will be preferred.

9

I predicted that you would say that…but the ospf cost in optical network is dynamic, and I must be absolutely sure that cost on wireless links is greater then on optical links…and I don’t want any uncertainity, because sometime it might happen that cost on wireless links is less then in optical network…

Is there any way to only advertise a.b.c.d/24 subnet to adjecent routers…?