Certbot hook scripts that allow to respond to DNS-01 challenges from Let's Encrypt by updating the DNS zone in an OVH account. There are several use cases for DNS challenge with Certbot. For example, when the server or machine that needs a certificate is not directly accessible from the internet; this way, you can secure machines and services in your internal network or company domain, even behind a firewall or VPN. Another example for this is to automatically deploy certificates to servers that for any reason cannot perform their challenges, like CDNs or other servers that for any reason cannot run Certbot. In this case you would need more automation to deliver the certificates securely to those hosts, but it's not the scope of this project.