In order to perform SSL termination on load balancers, DigitalOcean offers two types of SSL certificate management.
Custom: User-generated certificates may be uploaded to DigitalOcean where they will be placed in a fully encrypted and isolated storage system.
Let’s Encrypt: Certificates may be automatically generated by DigitalOcean utilizing an integration with Let’s Encrypt, the free and open certificate authority. These certificates will also be automatically renewed as required.