Unwrap the SERVFAIL
Oct 30, 2020Anbang Wen
Summary
This post introduces Extended DNS Errors (EDE) as a new option within EDNS to provide more detailed information about DNS resolution failures, specifically for SERVFAIL responses. This allows clients to understand the root cause of failures (e.g., DNSSEC Bogus, Network Error) without altering the existing RCODE, maintaining backward compatibility. The 1.1.1.1 service has initial support for the draft version of EDE, and the post demonstrates its usage with `dig`.
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