You can now open ports in the firewall, using port numbers or service
names:
[customizations.firewall]
ports = ["22:tcp", "80:tcp", "imap:tcp", "53:tcp", "53:udp"]
Or enable/disable services registered with firewalld:
[customizations.firewall.services]
enabled = ["ftp", "ntp", "dhcp"]
disabled = ["telnet"]
If the template contains firewall --disabled it cannot be overridden,
under the assumption that it is required for the image to boot in the
selected environment.
(cherry picked from commit 4d35668ab5)
Related: rhbz#1718473