DNS

DNS 8 NXRRSET vs 23 BADCOOKIE

Both DNS 8 (NXRRSET) and 23 (BADCOOKIE) belong to the DNS Response Codes (RCODEs) category. 8 indicates that rR Set that should exist does not. A required resource record set is missing from the zone. Meanwhile, 23 means that bad or missing server cookie. The DNS COOKIE option in the request is absent, malformed, or does not match the server's expected value.

คำอธิบาย

RR Set that should exist does not. A required resource record set is missing from the zone.

เมื่อคุณพบเห็น

A DNS UPDATE prerequisite expected a certain RRset to exist (e.g., an MX record), but the zone does not contain it.

วิธีแก้ไข

Create the missing RRset in the zone before retrying the update, or change the prerequisite to not require its existence.

คำอธิบาย

Bad or missing server cookie. The DNS COOKIE option in the request is absent, malformed, or does not match the server's expected value.

เมื่อคุณพบเห็น

Your resolver sent a query without a valid server cookie, or the cookie has expired. This is part of the DNS COOKIE mechanism to prevent spoofed-source attacks.

วิธีแก้ไข

Retry the query — most resolvers automatically learn the correct server cookie from the first response. If the error persists, ensure your resolver supports RFC 7873 DNS Cookies.

ความแตกต่างหลัก

1.

DNS 8: RR Set that should exist does not. A required resource record set is missing from the zone.

2.

DNS 23: Bad or missing server cookie. The DNS COOKIE option in the request is absent, malformed, or does not match the server's expected value.

3.

You encounter 8 when a DNS UPDATE prerequisite expected a certain RRset to exist (e.g., an MX record), but the zone does not contain it.

4.

You encounter 23 when your resolver sent a query without a valid server cookie, or the cookie has expired. This is part of the DNS COOKIE mechanism to prevent spoofed-source attacks.

ควรใช้อันไหนเมื่อไร

For 8 (NXRRSET): Create the missing RRset in the zone before retrying the update, or change the prerequisite to not require its existence. For 23 (BADCOOKIE): Retry the query — most resolvers automatically learn the correct server cookie from the first response. If the error persists, ensure your resolver supports RFC 7873 DNS Cookies.

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