FireWall
[1] If the Firewall on the server is unnecessarry (for example, because some firewalls are allready running in your LAN ), then stop it like follows.
[root@dlp ~]# systemctl stop firewalld
[root@dlp ~]# systemctl disable firewalld
rm '/etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service'
rm '/etc/systemd/system/basic.target.wants/firewalld.service'
SELinux
[2] If you'd like to disable SELinux (Security-Enhanced Linux), configure like follows.
[root@dlp ~]# vi /etc/selinux/config
# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of these two values:
# targeted - Targeted processes are protected,
# minimum - Modification of targeted policy. Only selected processes are protected.
# mls - Multi Level Security protection.
SELINUXTYPE=targeted
[root@dlp ~]# reboot