dnsspof

Every domain has a single point of failure.
Find yours before it finds you.

dnsspof resolves a domain's nameservers, mail, and web endpoints, maps every IP to its Autonomous System, and shows where the redundancy quietly collapses onto one network, one provider, or one country.

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DNS

Nameserver count, ASN / provider / prefix / country diversity, anycast detection, DNSSEC.

Web

Origin count, CDN presence, single-IP and single-ASN exposure.

Mail

MX provider and network concentration across exchangers.

Network · BGP/ASN

The decisive test: do DNS and origin share one ASN, so a single outage takes name resolution down with the site — and leaves no way to fail over?

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