Linux - Ayuda..FirewallD is not running

[root@javier ~]# systemctl status firewalld
firewalld.service
Loaded: masked (/dev/null)
Active: inactive (dead)


Warning: Unit file changed on disk, 'systemctl daemon-reload' recommended.
[root@javier ~]# systemctl start firewalld
Failed to issue method call: Unit firewalld.service is masked.

Buenos dias javierd,
no acabo de entender cual es el problema,
podrias ser algo mas extenso?
que Linux utilizas?

https://fedoraproject.org/wiki/FirewallD/es