lab environment:
virtual machine
A Linux system server do DHCP server
Two win10 client
GNS3 virtual network software
Purpose:
In gns3 the analog implementation of DHCP relay service
(A) first with vmnet8 NAT network mode to install the DHCP service on a Linux system
1, using the yum repository Download dhcp service
[Root @ localhost ~] # yum install dhcp -y install dhcp service
2, all installed after the vmnet1,2,8 switched to the master mode only, the modified vmnet8 nat only mode to master mode and the automatic allocation dhcp local virtual closed network editor on the virtual machine
(B) build a service infrastructure in gns3 in which to configure a device
1, open structures gns3 two hosts, a server, a Layer 2 switching, a three switches. (Change the device to two, three boards, set sw2, sw3 device name, set the disk space 128MB, add Layer 2 services board) specific settings seen previously
2, the devices are connected as follows:
win1 sw2 is coupled to the vmnet2 f1 / 2
win2 sw2 is coupled to the vmnet8 f1 / 3
dhcp sw2 is coupled to the vmnet1 f1 / 1
sw2 of f1 / 0 is connected to sw3 f1 / 0
Setup is complete and fully open and display the port number
3, double-click to open the Layer 2 sw2 exchange division vlan
win10-1:vlan10 192.168.10.1/24
win10-2:vlan20 192.168.20.1/24
dhcp:vlan100 192.168.100.1/24
Double-click to open sw2 configure vlan
f1/1:vlan100
f1/2:vlan10
f1/3:vlan20
sw2#configure terminal 进入全局模式 sw2(config)#vlan 10,20,100 创建三个vlan sw2(config-vlan)#ex 退出vlan sw2(config)#do show vlan-switch brief 查看创建的vlan的信息
sw2(config)#interface f1/1 进入f1/1的接口模式 sw2(config-if)#switch mod access 设置access模式 sw2(config-if)#switch access vlan 100 将端口分配给vlan100中 sw2(config-if)#ex sw2(config)#interface f1/2 设置f1/2的接口模式 sw2(config-if)#switch mod access sw2(config-if)#switch access vlan 10 sw2(config-if)#ex sw2(config)#interface f1/3 设置f1/3的接口模式 sw2(config-if)#switch mod access sw2(config-if)#switch access vlan 20 sw2(config-if)#ex sw2(config)#do show vlan-sw b 查看vlan的划分信息
sw2(config)#interface f1/0 进入f1/0接口 sw2(config-if)#switch mod trunk 设置中继链路模式 sw2(config-if)#switch trunk encapsulation dot1q 选择封装类型为dot1q sw2(config-if)#ex sw2(config)#no ip routing 关闭路由功能 sw2(config)#do show int f1/0 switchport 查看接口f1/0的接口信息
4,双击打开sw3三层交换机进行配置
创建三个vlan10,20,100
将f1/0接口设置为trunk链路
设置vlan10的网关子网掩码192.168.10.1 255.255.255.0
设置vlan20的网关子网掩码192.168.20.1 255.255.255.0
设置vlan100的网关子网掩码 192.168.100.1 255.255.255.0
sw3(config)#vlan 10,20,100 创建三个vlan sw3(config-vlan)#ex 退出 sw3(config)#do show vlan-sw b 查看创建的vlan的信息
sw3(config)#int f1/0 进入接口f1/0 sw3(config-if)#switch mod trunk 设置为trunk链路 sw3(config-if)#switch trunk encapsulation dot1q 选择封装的类型 sw3(config-if)#ex 退出 sw2(config)#do show int f1/0 switchport 查看接口f1/0接口的信息
sw3(config)#int vlan 10 进入vlan10 sw3(config-if)#ip add 192.168.10.1 255.255.255.0 设置vlan10的网关及子网掩码 sw3(config-if)#no shut 开启vlan10 sw3(config-if)#ex sw3(config)#int vlan 20 设置vlan20 sw3(config-if)#ip add 192.168.20.1 255.255.255.0 sw3(config-if)#no shut sw3(config-if)#ex sw3(config)#int vlan 100 设置vlan100 sw3(config-if)#ip add 192.168.100.1 255.255.255.0 sw3(config-if)#no shut
sw3(config-if)#end sw3#show ip interface brief 查看vlan设置的网关信息
(三)配置Linux系统的dhcp服务器
1,先将Linux系统的ip更改为一个静态的地址
[root@localhost ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens33 设置ens33的网卡信息设置一个静态的IP地址
[root@localhost ~]# systemctl restart network.service 重启网络服务 [root@localhost ~]# ifconfig 查看当前的网卡信息
2,复制一份dhcp配置文件的模板到/etc目录下
[root@localhost ~]# cp /usr/share/doc/dhcp-4.2.5/dhcpd.conf.example /etc/dhcp/dhcpd.conf 复制一份dhcp的配置文件模板到etc下 [root@localhost ~]# vim /etc/dhcp/dhcpd.conf 设置dhcp的配置文件
[root@localhost ~]# systemctl start dhcpd 开启dhcp服务 [root@localhost ~]# systemctl status dhcpd 查看dhcp服务状态信息
(四)在网关中配置DHCP中继
sw3#conf t 进入全局模式 sw3(config)#int vlan 10 设置网关中的DHCP中继 sw3(config-if)#ip helper-address 192.168.100.100 sw3(config-if)#no shut sw3(config-if)#ex sw3(config)#int vlan 20 sw3(config-if)#ip helper-address 192.168.100.100 sw3(config-if)#no shut sw3(config-if)#ex sw3(config)#int vlan 100 sw3(config-if)#ip helper-address 192.168.100.100 sw3(config-if)#no shut
(五)在win1和win2客户机中获取DHCP自动分配的地址
1,打开win10-1的网络更改为自动获取IP地址
2,打开cmd命令输入命令ipconfig,查看ip地址(192.168.10.182),成功获取
3,打开win10-2的网络更改为自动获取IP地址
4,打开cmd命令输入命令ipconfig,查看ip地址(192.168.20.182),成功获取
5,使用ping测试是否和DHCP服务器互联互通,实验成功
实验结果:成功利用linux系统中的DHCP中继服务,自动分配不同网段内ip范围中的地址
扩展:如何利用DHCP服务固定给某客户机一个固定的IP地址?
1,打开win10-1客户机,使用ipconfig /all查看网卡的MAC地址并复制
2. Open a Linux system, edit dhcp server configuration file, and restart the service
[root @ localhost ~] # vim /etc/dhcp/dhcpd.conf edit information fixed IP assigned to dhcp configuration file [root @ localhost ~] # systemctl restart dhcpd.service restart the dhcp service
3, in win10-1 client test results
ipconfig / release to release the original IP address ipconfig / renew IP address and obtain
The results: the success of obtaining a fixed IP address, a successful experiment
thanks for reading
!!!