Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. https://crt.sh/?q=welzijnsmasseur.nl), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
My domain is: welzijnsmasseur.nl
I ran this command: Get a certificate via GUI from Synology NAS
It produced this output: Failed to connecto to Letâs Encrypt. Please make sure the domain name is valid.
My web server is (include version): Synology Webstation
The operating system my web server runs on is (include version):
My hosting provider, if applicable, is: mijndomein.nl
I can login to a root shell on my machine (yes or no, or I donât know): I donât know
Iâm using a control panel to manage my site (no, or provide the name and version of the control panel): Yes
The version of my client is (e.g. output of certbot --version or certbot-auto --version if youâre using Certbot): I donât know
On the same synology NAS I am running 2 different websites with a certificate from Letâs Encrypt without any problem. Only difference those domains are hosted by a different hosting company.
Hi @baspeels
there is a check of your domain ( https://check-your-website.server-daten.de/?q=welzijnsmasseur.nl ):
There you see the problem.
You have ipv4- and ipv6 addresses:
| Host |
T |
IP-Address |
is auth. |
â Queries |
â Timeout |
| welzijnsmasseur.nl |
A |
81.204.230.39 |
|
|
|
| Rhenen/Provincie Utrecht/NL |
yes |
1 |
0 |
|
|
|
AAAA |
2a00:4e40:1:1::2:20b |
|
|
|
| Lelystad/Flevoland/NL |
yes |
|
|
|
|
| www.welzijnsmasseur.nl |
A |
81.204.230.39 |
|
|
|
| Rhenen/Provincie Utrecht/NL |
yes |
1 |
0 |
|
|
|
AAAA |
2a00:4e40:1:1::2:20b |
|
|
|
| Lelystad/Flevoland/NL |
yes |
|
|
|
|
But your http + /.well-known/acme-challenge has different answers:
http + ipv4 is redirected to https, http + ipv6 not. And ipv6 answers with a http status 200, not the expected status 404 - Not Found.
So
- remove your ipv6, then create a certificate, then fix your ipv6 (or)
- fix your ipv6
But Letsencrypt prefers ipv6, so that's critical.
Thanks for pointing me in the right direction, I removed ipv6 settings at domain registrar under dns settings. Recreated the certificate and that worked. I will test it for some days and renew it in a few days. Then I will try to fix the ipv6 settings, but tried to find my ipv6 address, but canât find it. I used whatsmyip.com
whatsmyip shows you the ip address of your local computer.
So if you don't have a configured ipv6, that can't work.
And that service looks wrong.
Your Public IPv4: 162.158.114.98
IPv6: 2a01:238:301b::1229
The ivp6 is correct, the ipv4 is completely wrong.
I get the same thing.
The websiteâs using Cloudflare, and the IPv4 IPs are Cloudflare IPs. It appears theyâre failing to use the X-Forwarded-For header or whatever and reporting Cloudflareâs proxy server IP as âyourâ IP.
Yep - 162.158.114.98 is Cloudflare Berlin. 
But Iâm not Cloudflare and I donât use it.