1. Install from web: https://get.acme.sh
Install https://github.com/Neilpang/acme.sh
curl https://get.acme.sh | sh
or
wget -O - https://get.acme.sh | sh
See https://github.com/Neilpang/acme.sh/wiki/Options-and-Params for available options.
curl https://get.acme.sh | ACME_USE_WGET=1 HTTPS_INSECURE=1 sh -s -- --home /opt/acme.sh --noprofile
or
wget -O - https://get.acme.sh | HTTPS_INSECURE=1 sh -s -- --home /opt/acme.sh --noprofile