A Record
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... authoritative for a domain whenever it encodes one into a packet. If
it is, then it will insert any A records it finds for that domain
into the additional information section of the answer until the
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If a client encounters a record with an unknown flag, it MUST ignore
it and move to the next Rule. This test takes precedence over any
ordering since flags can control the interpretation placed on fields.
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A novel flag might change the interpretation of the regexp and/or
replacement fields such that it is impossible to determine if a
record matched a given target.
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