Perhaps as most these days are using Anycast [1] to do failovers. It's faster and not subject to all the oddities that come with every application having its own interpretation of DNS RFC's most notably java and all its work-arounds that people may or may not be using and all the assorted recursive cache servers that also have their own quirks thus making Anycast a more reliable and predictable choice.
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Perhaps as most these days are using Anycast [1] to do failovers. It's faster and not subject to all the oddities that come with every application having its own interpretation of DNS RFC's most notably java and all its work-arounds that people may or may not be using and all the assorted recursive cache servers that also have their own quirks thus making Anycast a more reliable and predictable choice.
[1] - https://en.wikipedia.org/wiki/Anycast