18 Sep
2003
18 Sep
'03
2:22 p.m.
On Thu, 18 Sep 2003, Leo Bicknell wrote:
A truely robust anycast setup has two "addresses" (or networks, or whatever), but only one per site. From the momentary outage while BGP reconverges to the very real problem of the service being down and the route still being announced there are issues with all anycast addresses going to one site.
Yes, this is the fatal miscalculation in the ultradns setup. However, the other aspect, hiding most servers and only showing two at a time, isn't exactly the best idea ever either. First of all, it limits the number of usable DNS servers available at any specific location unnecessarily, and second, BGP metrics are a very poor substitute for RTT measurements.