Failed DVSNI Challenge although everything configured well, I guess


Hey there,
I am so glad to have found letsencrypt and I’ve been very excited of using it on my selfhostet webserver. Well, I cloned letsencrypt from github onto my ubuntu 15.10 Server and ran the standalone after stopping my well-working nginx-server. Me, my family and my friends never had problems connecting to it but letsencrypt (Port 80 is open and domain refers/points to the right page/server/ip). It says that:

Domain: www.el***
   Type:   connection
   Detail: Failed to connect to host for DVSNI challenge

,no matter if I am using the domain el*** or its subdomain www.el*** I am no pro, when it comes to connecting my server with a domain so I am proud it worked as fine as it did until now, but if you need further information, I am not too lazy to look it up :P. I guess there are different types of linking a server and a domain to each other and I choose the wrong one ? o.O
It would be very nice, if you could help me making my server more secure.


Are you using cloudflare stop it during the installation ? Its kinda hard to see the website with the *** :wink:
There are also alternative ways of getting a certificate such as webroot and other ACME clients.