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DNSSEC Validation Check

Check DNSSEC properly — including the broken-signature case a single query cannot see.

Domain

How this lookup works

The domain is queried twice: once normally, and once with checking disabled. That pair is what makes the answer meaningful. A single query returning the Authenticated Data flag tells you the resolver validated the chain — but its absence is ambiguous, because a non-validating resolver never sets it regardless of how well signed the domain is. Worse, the failure that actually matters is invisible in one query: when a domain is signed and its signatures have broken, a validating resolver returns SERVFAIL and the name is simply unreachable for everyone using one. Resolving with checking disabled and failing without it is exactly that case, and it is the outcome worth acting on immediately.

What the results mean

Secure
The AD flag was set — the resolver followed the chain from the root and every signature checked out.
Bogus
Resolves only with validation disabled. The domain is signed and broken, and unreachable for anyone using a validating resolver.
Insecure
Resolves, no AD flag. Most likely unsigned, but strictly this is ambiguous.
AD flag
Means this resolver validated. Its absence is not proof of anything on its own.

Common problems and fixes

Some people cannot reach my domain and others can
Check for the bogus state. A broken DNSSEC chain fails only for people using a validating resolver, which now includes Google, Cloudflare and most ISPs — so it looks intermittent and is not.
My domain shows as insecure but I enabled DNSSEC
The DS record at the registrar may not match the key at the DNS host. Both sides have to agree, and enabling it in one place alone leaves the domain unsigned.
Does DNSSEC encrypt my DNS queries?
No, and this is the common confusion. It signs answers so they cannot be forged. Encrypting the query is what DNS-over-HTTPS and DNS-over-TLS do.

Frequently asked questions

What does the AD flag actually mean?

That the resolver answering you validated the DNSSEC chain itself. It says nothing about the path between you and that resolver, and it is absent from any resolver that does not validate — which is why a single query cannot distinguish unsigned from unvalidated.

What happens if DNSSEC breaks?

The domain becomes unreachable for everyone using a validating resolver, which is now most people. It is one of the few DNS misconfigurations that takes a domain offline completely rather than degrading it.

Is DNSSEC the same as DNS-over-HTTPS?

No. DNSSEC signs the answer so it cannot be forged between the authoritative servers and the resolver. DNS-over-HTTPS encrypts the query between you and the resolver. Different threats, and you can have either without the other.

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