Relevant link:

I recommend adding the below text, as I've used this successfully numerous times on Red Hat based systems:

The DHCP daemon can be configured with command line options in the /etc/sysconfig/dhcpd file. For example DHCP can be bound to a single network interface.

[bash]# vi /etc/sysconfig/dhcpd

Set the following argument to provides queries/assignment on the indicated network interface.

# Command line options here

Rodd Ahrenstorff