On Sun, Nov 30, 2008 at 11:52 PM, Scott Brim <[EMAIL PROTECTED]> wrote: > The issue will rarely come up. In order for it to arise, a site > border router must come up cold with no knowledge of prefixes where it > wants to find its NTP servers. Once it maps these prefixes, which > will very probably be few and well-used, it will have mappings for > them until it comes up cold again. So as yet another alternatives, > avoid completely cold restarts, or give it what it needs via > configuration or synchronization. There are probably other > possibilities.
Scott, It need only expire the cached map entry for inactivity. Which it will tend to do over tens of minutes with no use and plenty of competition from other maps, something typical of the traffic pattern for NTP. Nor can you store the cached map for long: in a pull-cache system, cache expiration is your only guarantor of convergence. Everything else you throw at it is a heuristic that only works *most* of the time. That's one of the things that makes NTP good for illustrating this problem. I remind you about: http://www.ops.ietf.org/lists/rrg/2008/msg00465.html and the thread at: http://www.ops.ietf.org/lists/rrg/2008/msg00509.html Also, look at: http://bill.herrin.us/network/statechange.html for an explanation of why you can't cache entries for very long. Regards, Bill Herrin -- William D. Herrin ................ [EMAIL PROTECTED] [EMAIL PROTECTED] 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004 _______________________________________________ rrg mailing list [email protected] https://www.irtf.org/mailman/listinfo/rrg
