A NCP (nextcloudpi) server is stationed at downwind.duckdns.org
Safari returns:
Chrome returns:
A private Safari browser returns the expected NCP webpage.
I seek a troubleshooting procedure to diagnose the issue: I am wondering if there is a certificate issue.
The certificate for serving downwind.duckdns.org HTTPS connection has expired.
Curl:
$ curl -vvv https://downwind.duckdns.org ^[ * Trying 104.6.85.206:443... * Connected to downwind.duckdns.org (104.6.85.206) port 443 (#0) * ALPN, offering h2 * ALPN, offering http/1.1 * CAfile: /etc/ssl/certs/ca-certificates.crt * CApath: /etc/ssl/certs * TLSv1.0 (OUT), TLS header, Certificate Status (22): * TLSv1.3 (OUT), TLS handshake, Client hello (1): * TLSv1.2 (IN), TLS header, Certificate Status (22): * TLSv1.3 (IN), TLS handshake, Server hello (2): * TLSv1.2 (IN), TLS header, Finished (20): * TLSv1.2 (IN), TLS header, Supplemental data (23): * TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8): * TLSv1.2 (IN), TLS header, Supplemental data (23): * TLSv1.3 (IN), TLS handshake, Certificate (11): * TLSv1.2 (OUT), TLS header, Unknown (21): * TLSv1.3 (OUT), TLS alert, certificate expired (557): * SSL certificate problem: certificate has expired * Closing connection 0 curl: (60) SSL certificate problem: certificate has expired More details here: https://curl.se/docs/sslcerts.html Openssl:
$ openssl s_client -connect downwind.duckdns.org:443 -servername downwind.duckdns.org 2>/dev/null | openssl x509 -noout -dates notBefore=Nov 6 00:09:24 2024 GMT notAfter=Feb 4 00:09:23 2025 GMT Renew the certificate.
ERR_CERT_DATE_INVALIDpretty clearly points to a certificate issue.