Host key verification failed. scp: Connection closed TLS Version Tester — Free, no signup | Certfly — Watch your TLS certs so you don't have to.
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Free tools » TLS Version Tester

Free TLS protocol version probe

Test which TLS versions a host supports — TLSv1.0 through TLSv1.3. Identify legacy protocol exposure for PCI DSS / SOC 2 compliance.

Use host:port for non-standard ports (default 443).

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