facing problem in distribute-list for subnet filtering in OSPF

vipinkumar86 · ‎04-10-2012

Hello Friends,

I am facing problem in filtering subets between 2 OSPF neighbors by using distribute-list route-map , criteria for filtering subnets is route tag.

I have attached the config and output. Please help to share you feedback.

Thanks,

VK

Mahesh Gohil · ‎04-10-2012

Hi Vipin,

I am not 100%sure but you can try to change one route type as external to ...may be received from 10.230.3.34

at origin end because i don't think you have option to change LSA at receiver end.

Regards # Mahesh

vipinkumar86 · ‎04-10-2012

Thanks Mahesh for your feedback,

Yes , you are right, If I make subnets revceived from 10.230.3.34 as E2, then yes E1 routes will be preferred over E2 .

But I have limitations, as this topology it bit complex and I have to keep metric and route type same ( E1) on both both ASBR's , then I have only option to fix this at remote device

Thanks,

Vipin

Mahesh Gohil · ‎04-10-2012

In that case can you try below at remote end

match tag 63000

set metric-type type-2

and then clear the session.

Regards

Mahesh Gohil · ‎04-11-2012

Hi,

As per below link only option is for match and not set

http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/routmap.html

Regards

nkarpysh · ‎04-11-2012

Hello,

Please remember in OSPF distribute list can filter only routes sent from OSFP database to rouring table. Not the routes coming into OSPF DB. Thus as OSPF already received to LSAs and did SPF calculations and decided that both should go to GRT - you can either just filter one route to be completely out with ACL or prefix-list or leave both in. Metric manipualtion wont help here as route already coming from DB to GRT and decision was alredy taken.

http://www.cisco.com/en/US/partner/tech/tk365/technologies_q_and_a_item09186a0080094704.shtml#q12

You can think of other ways - as this seems to be a lab - I will let you find other ways for a sake of learning.

Nik

HTH,
Niko