AXFR
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... AXFR ...
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When the poll shows that the zone has changed, then the secondary server
must request a zone transfer via an AXFR request for the zone. The AXFR
may cause an error, such as refused, but normally is answered by a
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... When the poll shows that the zone has changed, then the secondary server
must request a zone transfer via an AXFR request for the zone. The AXFR
may cause an error, such as refused, but normally is answered by a
sequence of response messages. The first and last messages must contain
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... the secondary to construct a copy of the zone. Because accuracy is
essential, TCP or some other reliable protocol must be used for AXFR
requests.
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