Every Uberspace comes with enforced HTTPS its own certificate. Your external domains as well as the default domains, are automatically provided with a free certificate from Let’s Encrypt. In combination with our default security headers, this ensures that you and your users always use a secure connection to prevent eavesdropping and injection of unwanted content.

Let’s encrypt

We use lua-resty-auto-ssl to issue Let’s Encrypt certificates for every external domain that is connected to a Uberspace. This happens automagically when a domain (Host header) is first seen by our webserver. For privacy reasons every domain gets its own certificate. We also handle the renewal, certificates will be renewed if they expire in less than 30 days.

Certificate Access

Once a certificate has been generated, you can find all relevant files in ~/etc/certificates. This includes your certificate chain - <domain>.crt - as well as the private key - <domain>.key. If you do not make use of our webserver, you can copy or directly use these files in your application. If you use PHP, static files or web backends, we handle HTTPS for you and there is no need to do anything.


Certificates issued by let’s encrypt have a short life of 90 days. We renew certificates when they are 60 days old. In practice, the provided files will change every 1-2 months.

Make sure to either restart your service once a month, or watch the files for changes and restart accordingly. Otherwise your service will use an outdated, invalid certificate.