I managed to install Letsencrypt on my local machine (ubuntu 12.04) and it is functional.
sudo ./letsencrypt-auto certonly --manual
answered the questions.
Now I have 3 files in directory
Plesk lets me enter
"private key" that is clear
What file is entered where?
What is chain and fullchain for?
I used to buy certificates but would now like to use letsencrypt for most sites.
I am rather new to this.