The reason the local-preference is set is to make SURE the path is preferred through R8. Yes, by default it very well may go through R8 but we want to make absolutely certain that is the case, so local preference is used. In the lab, so long as you accomplish what is asked you are fine. In this particular case, it is more of a sure deal sort of thing.
On Sat, Apr 24, 2010 at 2:28 PM, RAragon <[email protected]> wrote: > HELP IPX community and Instructors, > > > Page 346 of the solution guide shows the completion of a task to ensure that > R7 transits R8 when going to Networks originating in AS10101. > > I understand the task, but was it needed? When I did the lab, I tested to > see if the path was as stated and it was so I did not see the point of > adding any configuration as a fail-safe. Please let me know if ther was a > reason to issue the commands in the SG (besides for practicing how to > manipulate Local Preference).Who knows maybe I am missing some routes for r4 > at this stage. If the solution had a verification command to set the > commands up it would eliminate my question, assuming the verification showed > the need for doing the commands specified. > > Here is my Pod's output, which shows all R7's paths to AS 10101 going to R8 > already (before me entering any local preference changes): > > > R7#sho ip bgp regexp _101010$ > > R7#sho ip bgp regexp _10101$ > BGP table version is 291, local router ID is 200.0.0.7 > Status codes: s suppressed, d damped, h history, * valid, > best, i - > internal, > r RIB-failure, S Stale > Origin codes: i - IGP, e - EGP, ? - incomplete > > Network Next Hop Metric LocPrf Weight Path > *>i150.100.41.0/24 150.100.78.8 0 100 0 10101 i > *>i150.101.12.0/24 150.100.78.8 0 100 0 10101 i > *>i150.101.13.0/24 150.100.78.8 0 100 0 10101 i > *>i150.101.14.0/24 150.100.78.8 0 100 0 10101 i > *>i200.0.0.11/32 150.100.78.8 0 100 0 10101 i > *>i200.0.0.12/32 150.100.78.8 0 100 0 10101 i > *>i200.0.0.13/32 150.100.78.8 0 100 0 10101 i > *>i200.0.0.14/32 150.100.78.8 0 100 0 10101 i > R7# > R7# > > Okays so I realized that it would be a good idea to do the same command on > R2 to see what he saw... it turned out R2's BGP peering to R4 was in the > "active" state. Since I was working on a lab from a reload (I previously > worked on BGP labs) I was stung by the R2 Point-2-point issue that comes up > all the time when starting a lab (built in trouble-shooting). > > now with R4 redistributing AS 10101, here is the current r7 output (it still > shows R8 as the next hop): > > R7#sho ip bgp regexp _10101$ > BGP table version is 553, local router ID is 200.0.0.7 > Status codes: s suppressed, d damped, h history, * valid, > best, i - > internal, > r RIB-failure, S Stale > Origin codes: i - IGP, e - EGP, ? - incomplete > > Network Next Hop Metric LocPrf Weight Path > * i150.100.41.0/24 150.100.78.8 0 100 0 10101 i > * 150.101.12.0/24 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 150.101.13.0/24 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 150.101.14.0/24 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 200.0.0.11/32 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 200.0.0.12/32 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 200.0.0.13/32 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > * 200.0.0.14/32 200.0.0.6 0 109 10101 i > *>i 150.100.78.8 0 100 0 10101 i > R7# > > So my question is still valid.... Are we setting local preference just for > fun/practice or is there something I am missing? > > Thanks IPX > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > -- Regards, Joe Astorino - CCIE #24347 Sr. Technical Instructor - IPexpert Mailto: [email protected] Telephone: +1.810.326.1444 Live Assistance, Please visit: www.ipexpert.com/chat eFax: +1.810.454.0130 IPexpert is a premier provider of Self-Study Workbooks, Video on Demand, Audio Tools, Online Hardware Rental and Classroom Training for the Cisco CCIE (R&S, Voice, Security & Service Provider) certification(s) with training locations throughout the United States, Europe, South Asia and Australia. Be sure to visit our online communities at www.ipexpert.com/communities and our public website at www.ipexpert.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
