#monitoring

Check DNS propagation by querying a record across several major public resolvers at once — Google (8.8.8.8), Cloudflare (1.1.1.1), AdGuard and dns.sb — and seeing whether they all return the same answer. Pass a domain and a record type and the service queries every resolver in parallel and reports each resolver's answers, whether they are consistent (the change has fully propagated) or still differ (mid-propagation, stale caching or split-horizon DNS), the number of distinct answer sets and the union of all answers. Supported record types: A, AAAA, CNAME, MX, TXT, NS, SOA, SRV, CAA and PTR. A single-resolver endpoint queries one named resolver on its own, and a failing resolver is reported per-resolver without failing the whole call. Live DoH (DNS-over-HTTPS) JSON queries, always current. Built for verifying DNS changes after a migration or launch, debugging split-horizon or stale-cache issues, and uptime/propagation monitoring. A DNS propagation checker — distinct from single-resolver record lookup (dns), the email-authentication analyzer (emailsec) and WHOIS (whois). No upstream key, no cache.

api.oanor.com/dnspropagation-api

Check whether a host or website is reachable from dozens of locations around the world as an API, powered by check-host.net. Run an ICMP ping, an HTTP request, a TCP-port connect or a DNS resolution from many countries at once and get a per-node breakdown — reachable or not, response time, resolved IP, HTTP status code or DNS records — plus an aggregate "reachable from X of N nodes". Perfect for answering "is it down for everyone, or just me?", monitoring global uptime and latency, verifying CDN and geo-routing, debugging firewalls and regional blocks, and powering status pages. Also lists every available worldwide check node. No accounts, no agents to install.

api.oanor.com/hostcheck-api

Check any website's SSL/TLS certificate as an API. Pass a domain and the service performs a live TLS handshake and returns the certificate's subject and issuer, the validity window, the exact number of days until it expires, whether it is currently valid and trusted by a standard CA chain, the negotiated TLS protocol, serial number, SHA-256 fingerprint, key size and the full list of Subject Alternative Names (SANs). A lean expiry endpoint returns a simple ok / expiring_soon / expired status, perfect for uptime and certificate-expiry monitoring, dashboards, CI checks and security tooling. Self-contained — no third-party service. IP addresses and internal hosts are not supported.

api.oanor.com/sslcheck-api