It shows:
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator apache, Installer apache
Cert is due for renewal, auto-renewing…
Renewing an existing certificate
Performing the following challenges:
http-01 challenge for crbox.campo-randale.de
Waiting for verification…
Challenge failed for domain crbox.campo-randale.de
http-01 challenge for crbox.campo-randale.de
Cleaning up challenges
Some challenges have failed.
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):
apache 2.4
The operating system my web server runs on is (include version):
openSUSE LEAP 15.1
The version of my client is (e.g. output of certbot --version or certbot-auto --version if you’re using Certbot):
certbot 0.36.0
In 2018 we introduced several new features, including ACMEv2 support and wildcard certificates. We’ve got some exciting features planned for 2019.
The feature we’re most excited about is multi-perspective validation. Currently, when a subscriber requests a certificate, we validate domain control from a single network perspective. This is standard practice for CAs. If an attacker along the network path for the validation check can interfere with traffic they can potentially cause certificates to be issued that should not be issued. We’re most concerned about this happening via BGP hijacking, and since BGP is not going to be secured any time soon, we needed to find another mitigation. The solution we intend to deploy in 2019 is multi-perspective validation, in which we will check from multiple network perspectives (distinct Autonomous Systems). This means that potential BGP hijackers would need to hijack multiple routes at the same time in order to pull off a successful attack, which is significantly more difficult than hijacking a single route.
So your domain may be checked via different ip addresses - worldwide.
PS: A regional blocking is (my personal position) always wrong.