North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: DNS anycast considered harmful (was: .ORG problems this evening)
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.
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