DNS/RFC/8906/8.1.1について、ここに記述してください。

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8.1.1. Is the server configured for the zone?

Ask for the SOA record of the configured zone.
This query is made with no DNS flag bits set and without EDNS.

    We expect the SOA record for the zone to be returned in the answer section, the rcode to be set to NOERROR, and the Authoritative Answer (AA) and Query/Response (QR) bits to be set in the header; the Recursion Available (RA) bits may also be set [RFC1034]. We do not expect an OPT record to be returned [RFC6891]. Verify the server is configured for the zone:

    dig +noedns +noad +norec soa $zone @$server

    expect: status: NOERROR
    expect: the SOA record to be present in the answer section
    expect: flag: aa to be present
    expect: flag: rd to NOT be present
    expect: flag: ad to NOT be present
    expect: the OPT record to NOT be present


}}}