centos下搭建dhcp服务器
一、软件环境
CentOS release 6.5
dhcp-4.1.1-51.P1.el6.centos.x86_64
dhcp-common-4.1.1-51.P1.el6.centos.x86_64
二、网络拓扑
dhcp服务器--H3c交换机（7503）-- H3c交换机（5500）-- H3c交换机（3100）--dhcp客户端（办公电脑）
网段：
10.2.240.0/24
10.2.180.0/24
dhcp服务器ip：10.2.33.253
三、安装dhcp服务器
#yum -y install dhcp dhcp-common
#chkconfig dhcpd on
#cd /usr/share/doc/dhcp-4.1.1/
#cp dhcpd.conf.sampl /etc/dhcp/dhcpd.conf
#ifconfig
em1 Link encap:Ethernet HWaddr F0:4D:A2:01:7E:53
inet addr:10.2.33.253 Bcast:10.2.33.255 Mask:255.255.255.0
inet6 addr: fe80::f24d:a2ff:fe01:7e53/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:331357784 errors:0 dropped:0 overruns:0 frame:0
TX packets:301154296 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:226431663072 (210.8 GiB) TX bytes:124796979532 (116.2 GiB)
# cat /etc/sysconfig/dhcpd
# Command line options here
DHCPDARGS=em1
#cat /etc/dhcp/dhcpd.conf
# dhcpd.conf
#
# Sample configuration file for ISC dhcpd
#
# option definitions common to all supported networks...
option domain-name "test.com";
option domain-name-servers 202.106.196.115, 202.106.0.20;
default-lease-time 54000; #默认租约时间（秒）
max-lease-time 72000; #最大租约时间（秒）
log-facility local7;
subnet 10.2.240.0 netmask 255.255.255.0 {
range 10.2.240.11 10.2.240.100;
option routers 10.2.240.1;
option broadcast-address 10.2.240.255;
}
# This is a very basic subnet declaration.
subnet 10.2.180.0 netmask 255.255.255.0 {
range 10.2.180.101 10.2.180.150;
option routers 10.2.180.1;
option broadcast-address 10.2.180.255;
}
#为特定主机保留的ip地址
host fantasia {
hardware ethernet 00:25:64:A7:39:B4;
fixed-address 10.2.180.12;
}
#dhcp服务器网卡的网段，不加此网段，dhcp服务起不来
subnet 10.2.33.0 netmask 255.255.255.0 {
range 10.2.33.100 10.2.33.101;
option routers 10.2.33.1;
option broadcast-address 10.2.33.255;
}
#service dhcpd start
#netstat -anlp |grep dhcp
udp 0 0 0.0.0.0:67 0.0.0.0:* 14719/dhcpd
raw 0 0 0.0.0.0:1 0.0.0.0:* 7 14719/dhcpd
unix 2 [ ] DGRAM 13369026 14719/dhcpd
防火墙打开udp 67端口
四、交换机设置
登录7503交换机
[7503]dhcp relay server-group 1 ip 10.2.33.253
[7503]interface Vlan-interface 240
[7503-Vlan-interface240]dhcp select relay
[7503-Vlan-interface240]dhcp relay server-select 1
[7503]interface Vlan-interface 180
[7503-Vlan-interface180]dhcp select relay
[7503-Vlan-interface180]dhcp relay server-select 1
登录5500交换机
[5500]dhcp relay server-group 1 ip 10.2.33.253
[5500]interface Vlan-interface 240
[5500-Vlan-interface240]dhcp select relay
[5500-Vlan-interface240]dhcp relay server-select 1
[5500]interface Vlan-interface 180
[5500-Vlan-interface180]dhcp select relay
[5500-Vlan-interface180]dhcp relay server-select 1
五、测试
修改客户端电脑ip为自动获得模式，获得ip成功。
原文地址：http://bristol.blog.51cto.com/1004110/1873561
