Hi all, hope you can help. I used Let’s Encrypt on my Synology NAS for a while now. I always used standard ports (5000 and 5001 for HTTP and HTTPS respectively), but recently changed this to HTTPS-only on port 443 for security + convenience since a lot of corporate firewalls block the standard ports. This works fine, I am very happy with this.
DNS is (afaik) correctly configured. Port 80 and 443 are open and accessible.
My domain is:
I ran this command:
DSM Control Panel > Security > Certificate. Add/replace certificate > Let’s Encrypt.
Domain name: nas.clubweltevree.nl
Alternative name: none
It produced this output: Failed to connect to Let’s Encrypt, make sure the domain name is valid. I also tried with
Domain name: clubweltevree.nl
Alternative name: nas.clubweltevree.nl
this produced the same error.
My web server is (include version):
Synology DS NAS
The operating system my web server runs on is (include version):
DSM 6.0.2 (latest update)
My hosting provider, if applicable, is:
I can login to a root shell on my machine (yes or no, or I don’t know):
I’m using a control panel to manage my site (no, or provide the name and version of the control panel):
Yes, DSM UI
I hope someone can help me to solve this problem!