Feb 27, 2005 Radu at ohmi said:
"Say that you have a vanity domain record that references 3 MX's (#1 has
2A records, #2 has 3A records, and #3 has 2A records). This adds up to
That depends on the MTA. With the MX response, an MTA could query for only
the A record of the first MX RDATA field, and attempt delivery. So that's
just two queries minimum. It would kinda stupid for an MX always to resolve
initially all MX RDATA fields, but that doesn't mean it's not done.
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