On Aug 16, 2010, at 8:33 PM, Ole Troan wrote: >>>>>>> please ping my router, it's interface address is: >>>>>>> fe80::20e:cff:fe5c:b001/64 >>>>>>> >>>>>>> my monitoring system can't ping this to ensure liveness of the >>>>>>> interface either :( >>>>>> but they can ping whatever global /128 you put on that interface, so why >>>>>> doesn't that solve the problems? >>>>> Because you are then using one set of addresses for protool peerings >>>>> and another one for global ping - thus making life more complicated >>>>> for the operator. >>>> is that any more "complicated" (I don't quite understand that argument) >>>> than using IS-IS? >>>> >>> >>> Yes. >> >> yes. I tried something close to it 5 years ago and it was hell. > > how? Jared's "Yes" doesn't exactly help my understanding why this is > operationally complex.
You're comparing using ISIS as an IGP with utilizing non-unique (link-local) and non-globally-addressable IPs with each other. I honestly am having a hard time comprehending where you are going. link-local addresses have a very-limited use (and in some cases no use at all in the backbone that we operate). While they are useful for communicating on-link, the use (and preference) of a globally unique IP has greater intrinsic value. In the case of a /127 (we actually set the links as /128's on one vendor to avoid the ping-pong issue) you have two routers (or hosts) trying to talk to each other. Anything else on-link promotes unnecessary router chatter. - Jared -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
