1. Preparation

Make sure you backup all your previous configurations in the following locations:

/etc/dhcp
/etc/named.conf
/var/named/*
/var/lib/tftpboot/*

Once you have backed up of your existing configuration files, delete the original files from the master node and stop the following services:

[root@master ~]# systemctl stop dhcpd
[root@master ~]# systemctl stop httpd
[root@master ~]# systemctl stop named