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DNS Validation

I wonder if they will also be able to tag domains/addresses as potential spam-bots.

It flagged my favorite fake email that does have valid A record, but no MX record 'example@example.com' as invalid.

The email spec allows for missing MX records, it should fallback to use the A record to deliver instead.

Hopefully they aren't invalidating domains that don't have an MX record.

Hi fsckin, example@example.com fails because while we do fallback to A records, no mail exchanger responds to us, so no one can actually receive mail at that inbox which is why we mark it as invalid.

Just curious: is this a one-time immediate check for an MX that responds?

Say, for example, that example.com has only a single MX and for whatever reason (server is down, network connectivity is broken, etc.) it is unreachable or unresponsive at the exact time you test. Would that constitute a "fatal error" in your validation process?

If there is a single MX RR but it "expands" to multiple hosts (multiple A RRs), do you test a second one if the first doesn't respond?

TIA!

Anything @example.com is actually invalid due to it being reserved by RFC 2606.

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