DNS for sending domains — each domain's own nameservers first, SPF evaluated, DNS provider named

FeatureEmailService
Shipped
September 16, 2026 at 5:37 PM UTC
Author
Kamo
Commit
25815a1

LiveDnsResolver asks the zone's authoritative nameservers (found through 1.1.1.1/8.8.8.8), so a record a member just saved at their DNS provider is seen at once rather than after a resolver's negative cache expires; it falls back to the public resolvers on a referral or a timeout, and retries over TCP when an answer does not fit a datagram (dnsjava 3.5 fails to parse google.com's truncated TXT otherwise). SpfEvaluator evaluates a domain's policy for one IPv4 address as a receiving server would (RFC 7208: **************** redirect, the 10-lookup and 2-void-lookup limits), so a CNAME to contact.kamocrm.com, an include, or a bare ip4 all read the same. DnsProviders names the company running a zone's DNS from its nameservers, for provider-specific instructions.

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