Hello! First of all thank you very much for the support. Sorry to create another thread on the same topic, but after reading some time in the community I have not found a solution to my problem.
Before detailing my assembly, I would like to explain it, I have a nas unit mounted behind two routers, the one from the internet company in bridge mode -innbox g64- and a -tplink archer c1200- working as a router. The case is that the WAN has dynamic ip and I have created a subdomain with cname that points to a ddns service (duckdns) Previously I tried it with the tplink ddns service until thanks to another community thread I could read that they offer a nefarious service that cannot be used, so I decided to change to the duckdns service that I read success stories with this ddns provider.
But I can't do it in nas, I always get a let'sencrypt connection error with the domain, I can assure that I have the ports open and redirected, I can access it from the outside without problems and that I have tried to review the solutions offered in others community threads, but I can't get it to finish correctly.
I have even come to understand a little how the https://check-your-website.server-daten.de tool works, seeing in my case that it creates the certificates but in the unit it always gives me that error until the limit reaches of requests
Well without lengthening more I detailed my assembly:
My domains are:
My main domain is: rodriguezcaroabogados.com
But as I have detailed previously for this process I have created a subdomain (CNAME) that points towards a ddns service (duckdns) which would be the important ones for the case:
My main subdomain is: intranet.rodriguezcaroabogados.com
My ddns service domain is: rcaintranet.duckdns.org
I ran this command:
Create a new certificate NAS: Security / Certificates panel.
I am asked to fill in the following details.
Domain Name: intranet.rodriguezcaroabogados.com
Subject Alternative Name: rcaintranet.duckdns.org
It produced this output:
The error I get when I click on Next is
"Failed to connect to Let's Encrypt. Please make sure the domain name is valid"
The operating system my web server runs on is (include version): Nas Synology DSM 6.2.3-25426 Update 3
I would like to receive help to avoid having to continue wasting the resource of being able to create certificates that end in an error and not being able to use them
Letsdebug ok: https://letsdebug.net/intranet.rodriguezcaroabogados.com/404067
Verified access from outside
Ports opened and redirected correctly to nas ports, tested on https://www.yougetsignal.com/tools/open-ports/ (80 open, 443 open)
I appreciate some errors in the https://check-your-website.server-daten.de/?q=intranet.rodriguezcaroabogados.com tool, but I can't understand them, if someone can help me, I appreciate it.
Happy New Year