alias s="sudo systemctl"

function instalar() {
    yum list installed "$1" &>/dev/null && echo "$1 já instalado" || sudo yum install -y "$1"
}

function ativar_firewall() {
    instalar iptables-services
    s stop firewalld
    s disable firewalld
    s mask firewalld
    s enable iptables
    sudo iptables -F
}