Your Caddyfile doesn’t seem to include any DuckDNS configuration. Because of that, Caddy is attempting to obtain its certificate via TLS-ALPN-01 challenge, but it’s failing since your Caddy instance isn’t reachable from the Internet to complete the challenge.
Try searching this forum for other DuckDNS posts—you might find something relevant about using the DuckDNS module. For example:
Thank you, it is now connecting to the service, but now I have a new issue where Caddy won’t connect to any ports I’ve opened in my router settings and firewall.
<– PS C:\Users\stuff> cd C:\tools\Caddy
PS C:\tools\Caddy> ./caddy run --config Caddyfile
2025/01/13 08:21:21.759 ←[34mINFO←[0m using config from file {“file”: “Caddyfile”}
2025/01/13 08:21:21.763 ←[34mINFO←[0m adapted config to JSON {“adapter”: “caddyfile”}
2025/01/13 08:21:21.777 ←[34mINFO←[0m admin admin endpoint started {“address”: “localhost:2019”, “enforce_origin”: false, “origins”: [“//127.0.0.1:2019”, “//localhost:2019”, “//[::1]:2019”]}
2025/01/13 08:21:21.777 ←[34mINFO←[0m tls.cache.maintenance started background certificate maintenance {“cache”: “0xc000198380”}
2025/01/13 08:21:21.778 ←[34mINFO←[0m http.auto_https server is listening only on the HTTPS port but has no TLS connection policies; adding one to enable TLS {“server_name”: “srv0”, “https_port”: 443}
2025/01/13 08:21:21.778 ←[34mINFO←[0m http.auto_https enabling automatic HTTP->HTTPS redirects {“server_name”: “srv0”}
2025/01/13 08:21:21.779 ←[34mINFO←[0m http enabling HTTP/3 listener {“addr”: “:443”}
2025/01/13 08:21:21.779 ←[34mINFO←[0m http.log server running {“name”: “srv0”, “protocols”: [“h1”, “h2”, “h3”]}
2025/01/13 08:21:21.780 ←[33mWARN←[0m http HTTP/2 skipped because it requires TLS {“network”: “tcp”, “addr”: “:80”}
2025/01/13 08:21:21.780 ←[33mWARN←[0m http HTTP/3 skipped because it requires TLS {“network”: “tcp”, “addr”: “:80”}
2025/01/13 08:21:21.780 ←[34mINFO←[0m http.log server running {“name”: “remaining_auto_https_redirects”, “protocols”: [“h1”, “h2”, “h3”]}
2025/01/13 08:21:21.780 ←[34mINFO←[0m http enabling automatic TLS certificate management {“domains”: [“netflixkiller.duckdns.org”]}
2025/01/13 08:21:21.782 ←[34mINFO←[0m autosaved config (load with --resume flag) {“file”: “C:\Users\stuff\AppData\Roaming\Caddy\autosave.json”}
2025/01/13 08:21:21.782 ←[34mINFO←[0m serving initial configuration
2025/01/13 08:21:21.789 ←[34mINFO←[0m tls storage cleaning happened too recently; skipping for now {“storage”: “FileStorage:C:\Users\stuff\AppData\Roaming\Caddy”, “instance”: “4dd457a1-b542-40f8-b28b-edac5e2136f2”, “try_again”: “2025/01/14 08:21:21.789”, “try_again_in”: 86400}
2025/01/13 08:21:21.790 ←[34mINFO←[0m tls finished cleaning storage units –>