post_install() {
    # firewalld default zone drop
    if [[ -x "$(command -v firewall-cmd)" ]]; then
        if ! [[ "$(firewall-cmd --get-default-zone)" == "drop" ]]; then
            echo "INFO: Firewalld default zone changed"
            echo "INFO: Default firewall zone set to drop"
            echo "INFO: 'firewall-cmd --set-default-zone=drop'"
            firewall-cmd --set-default-zone=drop 2>/dev/null 1>/dev/null
        fi
    fi
}
