Another package to manage another package… welcome to new world … :D
Anyway but server need to keep rolling !!

This is tested with the RHEL7

yum install -y iptables-services
iptables-save > /etc/sysconfig/iptables .  # preserve existing rule
systemctl stop firewalld
systemctl mask firewalld
systemctl enable iptables
systemctl enable ip6tables
systemctl start iptables
systemctl start ip6tables

firewall-cmd --permanent --zone=public --add-rich-rule='
  rule family="ipv4"
  source address="192.168.12.0/25"
  port protocol="tcp" port="9200" accept'