So by default it's on, won't be visible in the running config unless you turn it off, and only distance vector protocols use it mostly.
Check. On Jul 16, 2011, at 3:22 PM, marc abel wrote: > I can't think of a situation where leaving split horizon on would > create a loop (it is a loop prevention technology), usually it would > just keep some routes from being learned on the spokes. You won't see > if set on the interfaces, the default is that it is enabled, but it > doesn't show in running config unless you disable it. > > On Sat, Jul 16, 2011 at 2:00 AM, Alef <[email protected]> wrote: >> Thanks Marc. >> Yeah i think you want to disable it usually on multipoint interfaces ? >> Although i haven't been doing that actively and things still seem to work ok >> (but then again i might just have introduced a loop in my network) >> >> Maybe i just haven't been paying attention, but i don't think i usually see >> it on the interfaces in the running config. Is it still enabled and we just >> don't see it ? >> >> Many thanks for your replies, it is much appreciated. >> Alef >> >> On Jul 15, 2011, at 11:29 PM, marc abel wrote: >> >>> It is on by default, on pretty much every int type and for every >>> protocol. OSPF however isn't affected by it because it really doesn't >>> advertise routes. It advertises LSA's from which routers then build >>> their routes from. So practically you just need to worry about the >>> distance vector protocols EIGRP and RIP. >>> >>> It is of particular importance to disable split horizon on the hub >>> when you have EIGRP or RIP running on a frame relay or PPP hub and >>> spoke topology. >>> >>> On Fri, Jul 15, 2011 at 3:54 PM, Alef <[email protected]> wrote: >>>> Hi Marc, >>>> I thought i did put the lab number in the subject header? >>>> >>>> I guess i have to do some more learning about split horizon. I didn't know >>>> it was by default enabled? Is it an EIGRP thing ? >>>> >>>> Thanks again, >>>> Alef >>>> On Jul 15, 2011, at 8:19 PM, marc abel wrote: >>>> >>>>> Because Cat4 is learning the route from BB2on it's vlan50 interface. >>>>> With split horizon enabled it will not advertise that route back out >>>>> it's vlan50 interface so you won't be able to learn it on R8 from >>>>> cat4. If Cat4 were originating the route, or learning it on a >>>>> different interface this wouldn't be an issue. >>>>> >>>>> Make sense? >>>>> >>>>> P.S. You may want to include the lab # in your questions. I got lucky >>>>> with your first question and guessed right. >>>>> >>>>> On Fri, Jul 15, 2011 at 12:48 PM, Alef <[email protected]> wrote: >>>>>> Anyone working on this task? Instead of getting the routes from BB2, R8 >>>>>> needs to get them from Cat4. >>>>>> >>>>>> The task does not really explain why we need to disable split horizon on >>>>>> vlan50 interface on cat4. >>>>>> Could anyone provide a good explanation ? >>>>>> _______________________________________________ >>>>>> For more information regarding industry leading CCIE Lab training, >>>>>> please visit www.ipexpert.com >>>>>> >>>>>> Are you a CCNP or CCIE and looking for a job? Check out >>>>>> www.PlatinumPlacement.com >>>>>> >>>> >>>> >> >> _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
