Issue a LetsEncrypt SSL certificate using acme.sh

lets-issue-cert.sh

#!/bin/bash

# Issue a LetsEncrypt SSL certificate using acme.sh
#
# ISPConfig 3 preparation:
# Enable the SSL option and Add a self-signed certificate on SSL tab within Sites/Domains to create the needed configurations.
#

if [ -z "$*" ]; then 
        printf "\n issue-cert.sh domain.com \n\n"
        exit 0
fi

acme="/usr/local/acme.sh/acme.sh"
webroot="/usr/local/ispconfig/interface/acme"
webssl="/var/www/${1}/ssl"
sslfilename="${1}"
#reloadcmd="service apache2 restart"
reloadcmd=""

issueargs="--issue -d ${1} -d webmail.${1} -d www.${1} -w ${webroot}"
installargs="--install-cert -d ${1} --cert-file ${webssl}/${sslfilename}.crt --key-file ${webssl}/${sslfilename}.key --fullchain-file ${webssl}/${sslfilename}.bundle --reloadcmd ${reloadcmd}"

echo ">${acme} ${issueargs}"
${acme} ${issueargs}

echo ">${acme} ${installargs}"
${acme} ${installargs}

Install acme.sh:

git clone https://github.com/Neilpang/acme.sh.git
cd acme.sh
./acme.sh --install --home /usr/local/acme.sh --certhome /etc/acme.sh --accountemail "me@here.com.br"

Fix crontab:
54 0 * * * /usr/local/acme.sh/acme.sh --cron --home /usr/local/acme.sh > /dev/null