If you are having difficulty obtaining an SSL certificate for the FastPanel control panel then it's worthwhile having a look to see if you have explicitly defined the DNS entries for your hostname within /etc/hosts.

One of our customers who run this particular control panel had the same issue and after looking around their control we were able to determine the reason for the certificate failing was because of the lack of DNS entries locally for the domain.

Open your host's file:

nano /etc/hosts

Now ensure it looks something like this:

# The following lines are desirable for IPv4 capable hosts
#127.0.0.1 myserver.mydomain.com myserver
IPv4_HERE myserver.mydomain.com myserver

# The following lines are desirable for IPv6 capable hosts
#::1 myserver.mydomain.com myserver
IPv6_HERE myserver.mydomain.com myserver

Take note! You can see that we commented out the addresses which point locally to 127.0.0.1 and ::1. Use the example above but obviously replace:

• IPv4_HERE - With your IPv4 address
• IPv6_HERE - With your IPv6 address
• myserver.mydomain.com - With your full server hostname
• myserver - With your server name (if using subdomain)

After you have completed these steps a LetsEncrypt SSL certificate should issue when going to:

Settings > Main > Panel Addresses > DOMAIN (SSL)

If it works leave your entries inside host's file so automatic renewal works.