Thanks for your detailed response, was very helpful, thought is not yet working, I added the @pruiz.eu at ionos and let’s see if that changes something in the next hours.
(I think it may take some time to update the changes right?)
The full logs now looks like this:
pablo@Pablo-hosting:~/caddy$ sudo caddy run
[sudo] password for pablo:
2023/01/30 09:31:13.811 INFO using adjacent Caddyfile
2023/01/30 09:31:13.814 INFO admin admin endpoint started {"address": "localhost:2019", "enforce_origin": false, "origins": ["//localhost:2019", "//[::1]:2019", "//127.0.0.1:2019"]}
2023/01/30 09:31:13.815 INFO http 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}
2023/01/30 09:31:13.816 INFO http enabling automatic HTTP->HTTPS redirects {"server_name": "srv0"}
2023/01/30 09:31:13.815 INFO tls.cache.maintenance started background certificate maintenance {"cache": "0xc00026f2d0"}
2023/01/30 09:31:13.828 INFO tls cleaning storage unit {"description": "FileStorage:/root/.local/share/caddy"}
2023/01/30 09:31:13.828 INFO tls finished cleaning storage units
2023/01/30 09:31:13.851 WARN pki.ca.local installing root certificate (you might be prompted for password) {"path": "storage:pki/authorities/local/root.crt"}
2023/01/30 09:31:13.853 INFO Warning: "certutil" is not available, install "certutil" with "apt install libnss3-tools" or "yum install nss-tools" and try again
2023/01/30 09:31:13.854 INFO define JAVA_HOME environment variable to use the Java trust
2023/01/30 09:31:14.871 INFO certificate installed properly in linux trusts
2023/01/30 09:31:14.872 INFO http enabling HTTP/3 listener {"addr": ":443"}
2023/01/30 09:31:14.873 INFO failed to sufficiently increase receive buffer size (was: 208 kiB, wanted: 2048 kiB, got: 416 kiB). See https://github.com/lucas-clemente/quic-go/wiki/UDP-Receive-Buffer-Size for details.
2023/01/30 09:31:14.873 INFO http.log server running {"name": "srv0", "protocols": ["h1", "h2", "h3"]}
2023/01/30 09:31:14.874 INFO http.log server running {"name": "remaining_auto_https_redirects", "protocols": ["h1", "h2", "h3"]}
2023/01/30 09:31:14.874 INFO http enabling automatic TLS certificate management {"domains": ["pruiz.eu", "localhost"]}
2023/01/30 09:31:14.874 INFO autosaved config (load with --resume flag) {"file": "/root/.config/caddy/autosave.json"}
2023/01/30 09:31:14.876 INFO serving initial configuration
2023/01/30 09:31:14.875 INFO tls.obtain acquiring lock {"identifier": "localhost"}
2023/01/30 09:31:14.875 INFO tls.obtain acquiring lock {"identifier": "pruiz.eu"}
2023/01/30 09:31:14.879 INFO tls.obtain lock acquired {"identifier": "pruiz.eu"}
2023/01/30 09:31:14.879 INFO tls.obtain obtaining certificate {"identifier": "pruiz.eu"}
2023/01/30 09:31:14.880 INFO tls.obtain lock acquired {"identifier": "localhost"}
2023/01/30 09:31:14.880 INFO tls.obtain obtaining certificate {"identifier": "localhost"}
2023/01/30 09:31:14.886 INFO tls.obtain certificate obtained successfully {"identifier": "localhost"}
2023/01/30 09:31:14.888 INFO tls.obtain releasing lock {"identifier": "localhost"}
2023/01/30 09:31:14.889 WARN tls stapling OCSP {"error": "no OCSP stapling for [localhost]: no OCSP server specified in certificate", "identifiers": ["localhost"]}
2023/01/30 09:31:15.655 INFO http waiting on internal rate limiter {"identifiers": ["pruiz.eu"], "ca": "https://acme-v02.api.letsencrypt.org/directory", "account": ""}
2023/01/30 09:31:15.657 INFO http done waiting on internal rate limiter {"identifiers": ["pruiz.eu"], "ca": "https://acme-v02.api.letsencrypt.org/directory", "account": ""}
2023/01/30 09:31:15.987 INFO http.acme_client trying to solve challenge {"identifier": "pruiz.eu", "challenge_type": "http-01", "ca": "https://acme-v02.api.letsencrypt.org/directory"}
2023/01/30 09:31:27.012 ERROR http.acme_client challenge failed {"identifier": "pruiz.eu", "challenge_type": "http-01", "problem": {"type": "urn:ietf:params:acme:error:connection", "title": "", "detail": "217.160.44.69: Fetching http://pruiz.eu/.well-known/acme-challenge/X6ilQfXBm3r92cT59dzhzvDs7xMnfIHPTQTIcCmBUs8: Timeout during connect (likely firewall problem)", "instance": "", "subproblems": []}}
2023/01/30 09:31:27.018 ERROR http.acme_client validating authorization {"identifier": "pruiz.eu", "problem": {"type": "urn:ietf:params:acme:error:connection", "title": "", "detail": "217.160.44.69: Fetching http://pruiz.eu/.well-known/acme-challenge/X6ilQfXBm3r92cT59dzhzvDs7xMnfIHPTQTIcCmBUs8: Timeout during connect (likely firewall problem)", "instance": "", "subproblems": []}, "order": "https://acme-v02.api.letsencrypt.org/acme/order/940206547/161846226527", "attempt": 1, "max_attempts": 3}
2023/01/30 09:31:28.380 INFO http.acme_client trying to solve challenge {"identifier": "pruiz.eu", "challenge_type": "tls-alpn-01", "ca": "https://acme-v02.api.letsencrypt.org/directory"}
2023/01/30 09:31:39.387 ERROR http.acme_client challenge failed {"identifier": "pruiz.eu", "challenge_type": "tls-alpn-01", "problem": {"type": "urn:ietf:params:acme:error:connection", "title": "", "detail": "217.160.44.69: Timeout during connect (likely firewall problem)", "instance": "", "subproblems": []}}
2023/01/30 09:31:39.388 ERROR http.acme_client validating authorization {"identifier": "pruiz.eu", "problem": {"type": "urn:ietf:params:acme:error:connection", "title": "", "detail": "217.160.44.69: Timeout during connect (likely firewall problem)", "instance": "", "subproblems": []}, "order": "https://acme-v02.api.letsencrypt.org/acme/order/940206547/161846250757", "attempt": 2, "max_attempts": 3}
2023/01/30 09:31:39.389 ERROR tls.obtain could not get certificate from issuer {"identifier": "pruiz.eu", "issuer": "acme-v02.api.letsencrypt.org-directory", "error": "HTTP 400 urn:ietf:params:acme:error:connection - 217.160.44.69: Timeout during connect (likely firewall problem)"}
2023/01/30 09:31:39.390 WARN http missing email address for ZeroSSL; it is strongly recommended to set one for next time
2023/01/30 09:31:50.331 INFO http generated EAB credentials {"key_id": "pD6Yg57GqowZTxexLqrsgQ"}
2023/01/30 09:32:13.217 INFO http waiting on internal rate limiter {"identifiers": ["pruiz.eu"], "ca": "https://acme.zerossl.com/v2/DV90", "account": ""}
2023/01/30 09:32:13.217 INFO http done waiting on internal rate limiter {"identifiers": ["pruiz.eu"], "ca": "https://acme.zerossl.com/v2/DV90", "account": ""}
2023/01/30 09:32:33.900 INFO http.acme_client trying to solve challenge {"identifier": "pruiz.eu", "challenge_type": "http-01", "ca": "https://acme.zerossl.com/v2/DV90"}
2023/01/30 09:33:02.126 ERROR http.acme_client challenge failed {"identifier": "pruiz.eu", "challenge_type": "http-01", "problem": {"type": "", "title": "", "detail": "", "instance": "", "subproblems": []}}
2023/01/30 09:33:02.126 ERROR http.acme_client validating authorization {"identifier": "pruiz.eu", "problem": {"type": "", "title": "", "detail": "", "instance": "", "subproblems": []}, "order": "https://acme.zerossl.com/v2/DV90/order/HzcWlkne_YwoMIGfrCkV2A", "attempt": 1, "max_attempts": 3}
2023/01/30 09:33:02.126 ERROR tls.obtain could not get certificate from issuer {"identifier": "pruiz.eu", "issuer": "acme.zerossl.com-v2-DV90", "error": "HTTP 0 - "}
2023/01/30 09:33:02.126 ERROR tls.obtain will retry {"error": "[pruiz.eu] Obtain: [pruiz.eu] solving challenge: pruiz.eu: [pruiz.eu] authorization failed: HTTP 0 - (ca=https://acme.zerossl.com/v2/DV90)", "attempt": 1, "retrying_in": 60, "elapsed": 107.247109963, "max_duration": 2592000}
I installed libnss3-tools as stated in the logs (no change)