DNS Tools

EDNS Support Check

Check whether the resolver supports EDNS extensions and inspect UDP size or DNSSEC flags.

About EDNS

EDNS extends classic DNS with larger message support and extra capabilities needed by modern DNS workflows. This page surfaces the EDNS capabilities returned by the backend.

Why teams run this check

• Verify whether EDNS is supported
• Inspect UDP payload sizing
• Review DNSSEC-related capability flags
• Spot compatibility limitations quickly

What to review

• EDNS support status
• Advertised UDP size and version
• DNSSEC OK signaling
• Technical details returned by the backend

Use the free public result to review signals quickly, then move into the full workspace for continuous monitoring and deeper evidence.

PRO

Nodes Observed12

Resolved Nodes11

Dual-stack Coverage4 / 12

Refresh Window5m

PREVIEW

warningDKIM key strengthreview

errorMTA-STS missingfix

check_circleTLS-RPT not configuredinfo

PRO

PREVIEW

Real-time alertsDISABLED

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