how to discard all ospf routes V7.1

RouterOS RouterOS beta
1

Does anyone have an example of a filter to discard all routes received via ospf in version 7.1?

2

You can’t discard all routes. Only “external” routes can be filtered.

3

Thanks for replying, do you have any example ospf filter for version 7.1? I tried some things here but they didn’t work.

4

Be more specific what did you try to do and what didn’t work.

5

/routing ospf instance
add in-filter-chain=ospf-in name=default-v2 router-id=172.16.9.255
/routing ospf area
add instance=default-v2 name=backbone-v2
/routing ospf interface-template
add area=backbone-v2 interfaces=loopback networks=172.16.9.255/32 passive priority=1
add area=backbone-v2 interfaces=l2tp_main networks=192.168.159.1/32 type=ptp
/routing filter rule

add chain=ospf-in disabled=no rule=“if (dst in 172.16.9.0/24 && dst-len==32 ) { accept } else { reject }”

[admin@Router-Escritorio] > /ip route/print where ospf=yes
Flags: D - DYNAMIC; I, A - ACTIVE; o, y - COPY
Columns: DST-ADDRESS, GATEWAY, DISTANCE
DST-ADDRESS GATEWAY DISTANCE
DIo 0.0.0.0/0 192.168.159.1%l2tp_main 110
DIo 10.228.64.0/30 192.168.159.1%l2tp_main 110
DIo 45.132.234.0/30 192.168.159.1%l2tp_main 110
DIo 45.132.234.4/30 192.168.159.1%l2tp_main 110
DIo 45.132.234.8/30 192.168.159.1%l2tp_main 110
DIo 45.132.234.19/32 192.168.159.1%l2tp_main 110

I need to discard these routes

6

Filter is working properly here. There is no option in ROS v7 to completely discard prefix. You can only reject (exclude prefix from being elected as best route).

7

In my scenario the filters do absolutely nothing, the routes remain exactly as they are when I enable the filter.

8

Check /routing/route print, OSPF routes should have F flag which means that those routes are filtered (rejected).