I am trying to figure out a way to install a letsencrypt SSL cert for webmin. So that I can access webmin using https.
This server runs many services on various dockers and I wanted to use webmin to monitor it. Webmin is installed to listen on a non standard (not 10000) port.
There is no webserver other than the webmin internal webserver and I don’t want to install one.
So how do I get letsencrypt to install a cert for the webmin server connection?
The challenge response form the acme client for letsencrypt seems to be trying to talk to standard HTTP port on the FQDN but of course there is nothing there as the webmin server is listening on a non standard port.
if you don’t have a webserver.
i think could use standalone mode (but yuo need to open port 80 TCP and i think also 443 TCP).
or you can write a script to use letsencrypt for use API DNS (example i use for cloudflare / ovh).
but is not implemented on webmin , but need to script in ssh…
For anyone else out there struggling to put a certificate on webmin this is how I did it on Ubuntu 20.04
snap install certbot
Once installed then
certbot -d YourFQDNForWebmin --manual --preferred-challenges dns certonly
Answer questions. Then add DNS TXT record as instructed. Once propagation has occurred then press continue.
Successfully received certificate.
Certificate is saved at: /etc/letsencrypt/live/YourFQDNForWebmin/fullchain.pem
Key is saved at: /etc/letsencrypt/live/YourFQDNForWebmin/privkey.pem
Cat those files to the terminal window.
Open webmin>Configuration>SSL>Upload Certificate
Then paste the Private Key into the text box and select entered below for the certificate and paste in the certificates from fullchain.pem then press save and webmin will install the new certificate.
Logout and in again and you should have a valid SSL certificate on the https connection to Webmin.