From: Cecil Jackson (cejackson1@comcast.net)
Date: Wed May 02 2007 - 07:41:36 ART
Thanks for the information very helpful.
-----Original Message-----
From: Salau,Olayemi [mailto:Olayemi.Salau@southampton.gov.uk]
Sent: Wednesday, May 02, 2007 6:08 AM
To: Cecil Jackson; ccielab@groupstudy.com
Subject: RE: REdistruting eigrp into ospf and avoiding loops
Hello,
I just posted something similar and your mail caught my eyes afterwards.
Although mine added a variation of RIP redistributed routes into EIGRP.
The option I personally love using is to tag the routes as they are
flowing across the processes on ASBR1/ASBR2 and deny them by matching
the respective tags as they flow through the partners-in-crime
ASBR2/ASBR1 respectively.
EIGRP takes care of itself via intEIGRP and extEIGRP AD concepts. That
is AD 90 is always preferred to AD 170
OSPF don't have this kind of concept and would normally use metric to
select the best path but this wouldn't prevent the routes from getting
being feedback though. All OSPF is concerned with is selecting the BEST
PATH to the route and it uses cost concept to achieve just that.
NOTE:- Routers uses 3 things to before adding routes into their RIBs
1. Longest Prefix 2. AD 3. Metric; In that other ... I think this is one
of the first things I learnt from the CCNP days.
However, if the task asks you to specifically prevent feedbacks, then
you can now think of a way to prevent the feedbacks. With reference to
your diagram, I will add these to each of the Routers:-
!
!
!
!
R1
router ospf 1
redistribute eigrp 100 route-map RED_EIGRP_OSPF subnets
!
router eigrp 100
redistribute ospf 1 metric 1 1 1 1 1 route-map RED_TAGGED_FRM_R3
!
route-map RED_EIGRP_OSPF permit 10
set tag 190
!
route-map RED_TAGGED_FRM_R3 deny 10
match tag 390
route-map RED_TAGGED_FRM_R3 permit 20
!
!
R3
router ospf 1
redistribute eigrp 100 route-map RED_EIGRP_OSPF subnets
!
router eigrp 100
redistribute ospf 1 metric 1 1 1 1 1 route-map RED_TAGGED_FRM_R1
!
route-map RED_EIGRP_OSPF permit 10
set tag 390
!
route-map RED_TAGGED_FRM_R1 deny 10
match tag 190
route-map RED_TAGGED_FRM_R1 permit 20
!
Many Thanks
This archive was generated by hypermail 2.1.4 : Fri Jun 01 2007 - 06:55:19 ART