In my case, my internet provider block the port 80 so the HTTPVAL fix wont work.   Since TLS-SNI challenge is deactivated and I can't use HTTP challenge, I'm obligated to use the DNS-01 challenge. I've found a way to use it with this docker and cloudflare. You will need those 2 scripts ( here ) and you will need to modify the script /etc/cont-init/50-config inside the docker.  docker exec -it [DOCKERNAME] /bin/bash vi /etc/cont-init.d/50-config In the file comment this line :