This short article explains how to easily disable DHCP on a CSN. This may be useful when transitioning from a CSN deployment to an SCS deployment while allowing both system to co-exist on the same private network. This would normally be problematic as both system would intercept DHCP requests in the PXE boot process.
Steps below are provided depending on the version of CentOS/RHEL. For 6.X versions, service is used, whereas 7.X systemctl is used.
SSH as root user to the CSN
Edit /etc/monit.conf and comment out the include line 246 so that it looks like this:
service monit restart
systemctl restart monit
Shut off DHCP:
service dhcpd stop
systemctl stop dhcpd
Verify DHCP is no longer running. Wait about a minute just to make sure that monit is not bringing DHCP back up.