Hi Shraddha, The situation I’m talking about is not when the same SID is advertised. It is simpler since the two IS-IS routers advertise different SIDs but use different algorithms. In this case, SR-domain ingress router local policy would dictate which topology and/or algorithm is selected.
Thanks, Acee On 11/20/17, 11:12 PM, "Shraddha Hegde" <shrad...@juniper.net> wrote: >Peter/Acee, > >Lets assume 1.1.1.1 is advertised by two nodes A and B. >A assigns a SID 10 :algo 200 >B assigns SID 10: algo 201 > >According to conflict resolution draft section 3.4 SID conflicts >Will be examined for algorithms and smallest algo wins >So remote nodes will program nexthops for SID 10 based on algo 200. > >I think this case is addressed in conflict resolution draft. >It would be better to handle all the conflict situation in conflict >resolution draft >Rather than putting different pieces in different drafts. > >Rgds >Shraddha > > > >-----Original Message----- >From: Peter Psenak [mailto:ppse...@cisco.com] >Sent: Tuesday, November 21, 2017 3:35 AM >To: Acee Lindem (acee) <a...@cisco.com>; >draft-hegdeppsenak-isis-sr-flex-a...@ietf.org >Cc: isis-wg@ietf.org >Subject: Re: ISIS SR Flexible Algorithm (Resending with alias correction) > >Hi Acee, > >On 20/11/17 19:19 , Acee Lindem (acee) wrote: >> Hi Shraddha, Peter, et al, >> >> The comment on the draft I had was that the conflict case where two >> ISIS routers advertise the same multi-homed prefix with a different >> algorithm needs to be covered. I wouldn’t try and optimize for this >> and would just do whatever is simplest but avoids loops (e.g., log the >> situation and prefer the path computed with the lowest numbered >>algorithm). > >prefix can have SIDs for many algorithms. Prefix-SID for one algorithm is >independent and orthogonal to prefix-SID for any other algorithm. > >There is no need for all sources of the multi-homed prefix to include the >same set of Algo-SIDs. Each source can advertise an independent set. > >The case is similar to Alg-0 SID, where prefix is advertised from two >different sources and one source advertise the Alg-0 SID and other does >not. > >thanks, >Peter > >> >> Thanks, >> Acee > _______________________________________________ Isis-wg mailing list Isis-wg@ietf.org https://www.ietf.org/mailman/listinfo/isis-wg
