wget https://dl.eff.org/certbot-auto

chmod a+x certbot-auto
#单域名
./certbot-auto certonly --email youremail@example.com --agree-tos --webroot -w 网站目录 -d 域名
#多域名
./certbot-auto certonly --email youremail@example.com --agree-tos --webroot -w 网站目录 -d 域名1 -d 域名2

#续期

./certbot-auto certonly --renew-by-default --email youremail@example.com -d yourdomainname

#nginxSSL段配置写法
ssl on;
ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers
"EECDH+CHACHA20:EECDH+CHACHA20-
draft:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5";  
ssl_prefer_server_ciphers on;
ssl_session_cache shared:SSL:10m;