具体到一个公司的网络环境中,不可能只有一个VLAN,更不可能对每个VLAN都架设一个DHCP服务器,这时就要做一个DHCP的中继,使得DHCP的广播可以通过VLAN


实验拓扑

三层交换机下面连接一台二层交换机,二层交换机下面连接一台DHCP SERVER、两台客户机Win10Win7。地址规划如下:

名称 IP地址
DHCP SERVER 192.168.100.100/24
Win10 DHCP(192.168.10.188/24)
Win7 DHCP(192.168.20.100/24)

配置方法

网关上配置ip helper-address

SW1(config)#int vlan 10
SW1(config-if)#ip add 192.168.10.1 255.255.255.0
SW1(config-if)#ip helper-address 192.168.100.100
SW1(config-if)#no sh
SW1(config-if)#ex

NETWORK 配置过程

SW2

  • 添加VLAN10、VLAN20、VLAN100
SW2#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
SW2(config)#vlan 10,20,100
SW2(config-vlan)#ex
SW2(config)#do show vlan-sw b VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa1/0, Fa1/1, Fa1/2, Fa1/3
Fa1/4, Fa1/5, Fa1/6, Fa1/7
Fa1/8, Fa1/9, Fa1/10, Fa1/11
Fa1/12, Fa1/13, Fa1/14, Fa1/15
10 VLAN0010 active
20 VLAN0020 active
100 VLAN0100 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
  • 端口添加到VLAN
SW2(config)#int f1/1
SW2(config-if)#sw m a
SW2(config-if)#sw a vlan 10
SW2(config-if)#ex
SW2(config)#int f1/2
SW2(config-if)#sw m a
SW2(config-if)#sw a vlan 20
SW2(config-if)#ex
SW2(config)#int f1/3
SW2(config-if)#sw m a
SW2(config-if)#sw a vlan 100
SW2(config-if)#ex
SW2(config)#do show vlan-sw b VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa1/0, Fa1/4, Fa1/5, Fa1/6
Fa1/7, Fa1/8, Fa1/9, Fa1/10
Fa1/11, Fa1/12, Fa1/13, Fa1/14
Fa1/15
10 VLAN0010 active Fa1/1
20 VLAN0020 active Fa1/2
100 VLAN0100 active Fa1/3
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
  • 配置Trunk
SW2(config)#int f1/0
SW2(config-if)#sw m t
SW2(config-if)#sw t e d
SW2(config-if)#ex
SW2(config)#do show int f1/0 switchport
Name: Fa1/0
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: Disabled
Access Mode VLAN: 0 ((Inactive))
Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1,10,20,100
Protected: false
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
  • 关闭路由功能。
SW2(config)#no ip routing

SW1

  • 配置Trunk
SW1#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
SW1(config)#int f1/0
SW1(config-if)#sw m t
SW1(config-if)#sw t e d
SW1(config-if)#ex
SW1(config)#do show int f1/0 switchport
Name: Fa1/0
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: Disabled
Access Mode VLAN: 0 ((Inactive))
Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1,10,20,100
Protected: false
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
  • 添加VLAN10、VLAN20、VLAN100
SW1(config)#vlan 10,20,100
SW1(config-vlan)#ex
SW1(config)#do show vlan-sw b VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa1/0, Fa1/1, Fa1/2, Fa1/3
Fa1/4, Fa1/5, Fa1/6, Fa1/7
Fa1/8, Fa1/9, Fa1/10, Fa1/11
Fa1/12, Fa1/13, Fa1/14, Fa1/15
10 VLAN0010 active
20 VLAN0020 active
100 VLAN0100 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
  • 配置网关地址、ip helper-address
SW1(config)#int vlan 10
SW1(config-if)#ip add 192.168.10.1 255.255.255.0
SW1(config-if)#ip helper-address 192.168.100.100
SW1(config-if)#no sh
SW1(config-if)#ex
SW1(config)#int vlan 20
SW1(config-if)#ip add 192.168.20.1 255.255.255.0
SW1(config-if)#ip helper-address 192.168.100.100
SW1(config-if)#no sh
SW1(config-if)#ex
SW1(config)#int vlan 100
SW1(config-if)#ip add 192.168.100.1 255.255.255.0
SW1(config-if)#ip helper-address 192.168.100.100
SW1(config-if)#no sh
SW1(config-if)#ex
SW1(config)#do show ip int b
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset administratively down down
FastEthernet1/0 unassigned YES unset up up
FastEthernet1/1 unassigned YES unset up down
FastEthernet1/2 unassigned YES unset up down
FastEthernet1/3 unassigned YES unset up down
FastEthernet1/4 unassigned YES unset up down
FastEthernet1/5 unassigned YES unset up down
FastEthernet1/6 unassigned YES unset up down
FastEthernet1/7 unassigned YES unset up down
FastEthernet1/8 unassigned YES unset up down
FastEthernet1/9 unassigned YES unset up down
FastEthernet1/10 unassigned YES unset up down
FastEthernet1/11 unassigned YES unset up down
FastEthernet1/12 unassigned YES unset up down
FastEthernet1/13 unassigned YES unset up down
FastEthernet1/14 unassigned YES unset up down
FastEthernet1/15 unassigned YES unset up down
Vlan1 unassigned YES unset up up
Vlan10 192.168.10.1 YES manual up up
Vlan20 192.168.20.1 YES manual up up
Vlan100 192.168.100.1 YES manual up up

DHCP 配置过程

安装 DHCP 服务

[root@localhost ~]# yum install dhcp -y

配置网卡静态 IP

[root@localhost ~]# cat > /etc/sysconfig/network-scripts/ifcfg-ens33 << EOF
> TYPE=Ethernet
> BOOTPROTO=static
> DEVICE=ens33
> ONBOOT=yes
> IPADDR=192.168.100.100
> NETMASK=255.255.255.0
> GATEWAY=192.168.100.1
> EOF
[root@localhost ~]# service network restart
Restarting network (via systemctl): [ OK ]
[root@localhost ~]# ifconfig ens33
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.100.100 netmask 255.255.255.0 broadcast 192.168.100.255
inet6 fe80::20c:29ff:febc:ab96 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:bc:ab:96 txqueuelen 1000 (Ethernet)
RX packets 2142 bytes 1951874 (1.8 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 691 bytes 64359 (62.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

编辑 DHCP 配置文件

[root@localhost ~]# cp /usr/share/doc/dhcp-4.2.5/dhcpd.conf.example /etc/dhcp/dhcpd.conf
cp: overwrite ‘/etc/dhcp/dhcpd.conf’? y
[root@localhost ~]# vim /etc/dhcp/dhcpd.conf
  • 7-8行可以配置DNS服务器名称、地址。
option domain-name "example.org";
option domain-name-servers 8.8.8.8;
  • 10-11行可以配置DHCP租约时间。
default-lease-time 600;
max-lease-time 7200;
  • 22行可以配置日志信息。
log-facility local7;
  • 27-40行配置网段信息。
subnet 192.168.10.0 netmask 255.255.255.0 {
range 192.168.10.100 192.168.10.200;
option routers 192.168.10.1;
} subnet 192.168.20.0 netmask 255.255.255.0 {
range 192.168.20.100 192.168.20.200;
option routers 192.168.20.1;
} subnet 192.168.100.0 netmask 255.255.255.0 {
range 192.168.100.100 192.168.100.200;
option routers 192.168.100.1;
}
  • 87-90配置指定IP地址分配。
host win10 {
hardware ethernet 00:0C:29:ED:26:F4;
fixed-address 192.168.10.188;
}

启动 DHCP 服务

[root@localhost ~]# systemctl start dhcpd
[root@localhost ~]# systemctl enable dhcpd
Created symlink from /etc/systemd/system/multi-user.target.wants/dhcpd.service to /usr/lib/systemd/system/dhcpd.service.
[root@localhost ~]# netstat -nuap | grep dhcpd
udp 0 0 0.0.0.0:67 0.0.0.0:* 42901/dhcpd
  • 关闭防火墙、SELinux
[root@localhost ~]# systemctl stop firewalld
[root@localhost ~]# setenforce 0

结果测试

Win10

Win7

Linux DHCP 中继的更多相关文章

  1. Linux配置DHCP服务器,DHCP中继配置

    配置dhcp服务器 第一步:配置网卡 第二步: 安装dhcp (需要先构建yum仓库,构建yum仓库的方法在之前的博客里有) 编写dhcp.conf文件 进去以后会出现这个内容 需要执行下面的内容将内 ...

  2. DHCP中继

    DHCP中继 要求: 假设公司现在有两个部门分别为 销售部门,生产部门 对这两个部门分配不同网段, 销售部门 192.168.1.0/24 生产部门 192.168.2.0/24 为了节约使用LINU ...

  3. 搭建DHCP服务器以及DHCP中继服务器

    一.DHCP服务器   1.首先配置DHCP服务器的IP地址(DHCP服务器网卡桥接在VMnet1)   .配置好IP后重启DHCP服务 3.安装DHCP服务器,在这里我用的是YUM安装的(关于YUM ...

  4. 如何搭建DHCP及DHCP中继服务器

    当局域网中有大量的主机时,如果逐台设置ip地址.默认网关.dns服务器地址时等网络参数,显然是一个费力也未必讨好的方法,这时使用DHCP的方式分发ip地址,能够动态配置各客户机的网络地址参数,大大减轻 ...

  5. 编写脚本实现DHCP服务与DHCP中继自动化执行

    编写脚本实现DHCP服务与DHCP中继自动化执行 本脚本是在liunx搭建DHCP服务器以及DHCP中继服务器实验环境下实现的https://www.cnblogs.com/yuzly/p/10539 ...

  6. liunx搭建DHCP服务器以及DHCP中继服务器

    liunx搭建DHCP服务器以及DHCP中继服务器 一.实验拓扑 二.实验条件 虚拟机取消VMnet1和VMnet8的dhcp动态获取ip地址,以免影响实验 DHCPserver 网关以及DHCP中继 ...

  7. CentOS7.3下关于DHCP中继代理服务器的详细配置

    DHCP服务器只作用于局域网同一网段内,客户端是通过广播消息来获得DHCP服务器响应后才能得到IP地址的,但广播消息不能跨越子网,那么如何让客户端获取到DHCP服务器提供的IP地址呢?这就是DHCP中 ...

  8. DHCP与DHCP中继原理与配置!(重点)

    一 .DHCP  服务概述 0:dhcp原理: 集中的管理.分配IP地址,使client动态的获得IP地址.Gateway地址.DNS服务器地址等信息,并能够提升地址的使用率.简单来说,DHCP就是一 ...

  9. Linux DHCP通过OPTION43为H3C的AP下发AC地址(总结)

    对于DHCP服务,可以在很多平台上进行设置.那么这里我们就主要讲解一下在Linux DHCP服务器上通过option 43实现H3C的AP自动联系AC注册的相关内容.原来的DHCP Server是放在 ...

随机推荐

  1. Linux performance monitor tool

    https://www.tecmint.com/command-line-tools-to-monitor-linux-performance/ https://www.tecmint.com/lin ...

  2. Ubuntu 16.04 catkin_make 常见操作

    参考博客:https://answers.ros.org/question/54178/how-to-build-just-one-package-using-catkin_make/ 1. catk ...

  3. 使用java计算数组方差和标准差

    使用java计算数组方差和标准差 觉得有用的话,欢迎一起讨论相互学习~Follow Me 首先给出方差和标准差的计算公式 代码 public class Cal_sta { double Sum(do ...

  4. 基于term vector深入探查数据

    1.term vector介绍 获取document中的某个field内的各个term的统计信息 term information: term frequency in the field, term ...

  5. CentOS上安装配置RabbitMQ Server

    1. 安装Erlang 由于rabbitmq是基于erlang语言开发的,所以必须先安装erlang. curl -s https://packagecloud.io/install/reposito ...

  6. [转]解决 gem install 安装失败

    链接地址:https://blog.csdn.net/weixin_42414461/article/details/85337465

  7. 【ML基础】t-SNE(t-distributed stochastic neighbor embedding)原理及推导

    前言 参考 1. t-SNE原理与推导: 完

  8. dockerfile使用

    一.构筑镜像命令 docker build -t test/nginx:v1.0 - prese/nginx:v1.0 -f /git/dockerfile . -t:指定存储库:镜像名和标签保存新镜 ...

  9. [Atcoder AGC037E]Reversing and Concatenating

    题目大意:有一个长度为$n$的字符串$S$,有$k$次操作,每次操作为把$S$变为$SS^R$(即翻转后再接在一起),然后从中选取一段长度为$n$的字串.问$k$次操作后,字典序最小的一种是什么.$n ...

  10. QRCode.js:使用 JavaScript 生成微信二维码

    https://www.runoob.com/w3cnote/javascript-qrcodejs-library.html 什么是 QRCode.js? QRCode.js 是一个用于生成二维码的 ...