centos 6.5
rpm：
dhcp-4.1.1-25.P1.el6.x86_64
dhcp-common-4.1.1-25.P1.el6.x86_64
服务：
/etc/rc.d/init.d/dhcpd
/etc/rc.d/init.d/dhcpd6
/etc/rc.d/init.d/dhcrelay
配置文件：
1. /etc/sysconfig/dhcpd
设置环境变量： DHCPDARGS， 缺省为空。
/etc/dhcp/dhcpd.conf
/etc/dhcp/dhcpd6.conf
/etc/openldap/schema/dhcp.schema
/etc/sysconfig/dhcpd
/etc/sysconfig/dhcpd6
/etc/sysconfig/dhcrelay
命令工具：
/usr/bin/omshell
/usr/sbin/dhcpd
/usr/sbin/dhcrelay