Re: [OSPF] ECMP from different areas of External Routes
"Jishnu Banerjee" <jishnub@ba-sys.com> Thu, 12 June 2008 08:04 UTC
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Thread-Topic: [OSPF] ECMP from different areas of External Routes
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From: Jishnu Banerjee <jishnub@ba-sys.com>
To: pranjalchakravarty@yahoo.co.in, ospf@ietf.org
Subject: Re: [OSPF] ECMP from different areas of External Routes
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If nexthops to the same destination prefix, are of same cost, path-type and same area, then ONLY ECMP comes into play else not. Now in case of External Routes(Refer Section 16.4) ecmp depends upon how you resolve the nexthops w.r.t reachibility to ASBR(incase the forwarding address is set to zero) else depends upon the nexthop through which the Forwarding Address can be reached. However the criterion (cost,path-type,area) still holds decide whether during SPF the same prefix should be installed as ECMP(multiple nexthops). Thanks, Jishnu Night after night Going round and round my brain His dream is driving me insane. In the corner of some foreign field The gunner sleeps tonight. What's done is done. We cannot just write off his final scene. Take heed of his dream. Take heed ________________________________ From: ospf-bounces@ietf.org [mailto:ospf-bounces@ietf.org] On Behalf Of Pranjal Chakravarty Sent: Thursday, June 12, 2008 12:37 PM To: ospf@ietf.org Subject: [OSPF] ECMP from different areas of External Routes I have a router with zebos implementation of ospf . Is ECMP is allowed in the router if the routes are learned from two diffrernt non backbone areas(Same cost),Or only one route will be installed in the router . The Route which is learnt from a higher area id will be installed in the router or both equal cost routes should be installed in the router. ________________________________ Meet people who discuss and share your passions. Join them now. <http://in.rd.yahoo.com/tagline_groups_7/*http:/in.promos.yahoo.com/grou ps/bestofyahoo/>
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- [OSPF] ECMP from different areas of External Rout… Pranjal Chakravarty
- Re: [OSPF] ECMP from different areas of External … Jishnu Banerjee