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. crt.sh | example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Starting new HTTPS connection (1): acme-v01.api.letsencrypt.org
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for arbeitnehmerkasse.at
Using the webroot path /var/www/arbeitnehmerkasse.at for all unmatched domains.
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. arbeitnehmerkasse.at (http-01): urn:acme:error:connection :: The server could not connect to the client to verify the domain :: Fetching http://
arbeitnehmerkasse.at/.well-known/acme-challenge/yknp2iwNwzUq9Uh4MKEnCxozTq4OVpm8pBkKdOPaQHk: Timeout during connect (likely firewall problem)
IMPORTANT NOTES:
The following errors were reported by the server:
Domain: arbeitnehmerkasse.at
Type: connection
Detail: Fetching http://arbeitnehmerkasse.at/.well-known/acme-challenge/yknp2iwNwzUq9Uh4MKEnCxozTq4OVpm8pBkKdOPaQHk:
Timeout during connect (likely firewall problem)
To fix these errors, please make sure that your domain name was
entered correctly and the DNS A/AAAA record(s) for that domain
contain(s) the right IP address. Additionally, please check that
your computer has a publicly routable IP address and that no
firewalls are preventing the server from communicating with the
client. If you're using the webroot plugin, you should also verify
that you are serving files from the webroot path you provided.
My web server is (include version):
?
The operating system my web server runs on is (include version):
Ubuntu (16.04.4)
My hosting provider, if applicable, is:
Google Cloud
I can login to a root shell on my machine (yes or no, or I don't know):
yes
I'm using a control panel to manage my site (no, or provide the name and version of the control panel):
As @JuergenAuer said, or your webserver is not listening on port 80 (it actually listens on port 443) or there is a firewall blocking the connection to your server using port 80. The reason you didn't notice it if you try to access http://arbeitnehmerkasse.de is because you configured your web server to send the Strict Transport Security header so your browser is always trying to reach that domain using https instead of http.
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
05049c91318b auko-nginx "nginx -g 'daemon of…" 7 days ago Up 3 hours 0.0.0.0:80->80/tcp, 0.0.0.0:443->443/tcp auko_gateway_1
84fb1bf8fc8e auko-webgui "nginx -g 'daemon of…" 7 days ago Up 3 hours 80/tcp auko_webgui_1
There are two docker container running: one on port 443 and one on 80. Do you have any suggestion on what I can do?
Because you are running a website (not a mailserver or something else), http should be open if someone types www.arbeitnehmerkasse.de without https. So you should fix that direct.