linux 操作系统下dhcrelay命令介绍和案例应用

dhcrelay是一个用于DHCP（动态主机配置协议）中继的命令，主要功能是在没有本地DHCP服务器的子网中转发DHCP请求。这使得不同子网的DHCP客户端能够与位于其他子网中的DHCP服务器进行通信。

`dhcrelay`命令介绍

dhcrelay命令的基本用法是接收来自DHCP客户端的请求，并将这些请求转发到指定的DHCP服务器。它通常用于大型网络环境中，当网络分为多个子网且每个子网都需要DHCP服务时，使用中继可以避免在每个子网中都部署DHCP服务器

基本语法

bash

dhcrelay [options] [server_ip]

server_ip: 指定一个或多个DHCP服务器的IP地址。
-i: 指定要监听的接口。
-p: 指定监听端口（默认是67）。

安装部署

root@meng:~# sudo apt-get install isc-dhcp-relay
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages were automatically installed and are no longer required:
cups-common libavahi-client3 libavahi-common-data libavahi-common3 libcups2 libevent-2.1-7
Use 'sudo apt autoremove' to remove them.
The following NEW packages will be installed:
isc-dhcp-relay
0 upgraded, 1 newly installed, 0 to remove and 226 not upgraded.
Need to get 116 kB of archives.
After this operation, 398 kB of additional disk space will be used.
Get:1 http://mirrors.tuna.tsinghua.edu.cn/ubuntu jammy-updates/universe amd64 isc-dhcp-relay amd64 4.4.1-2.3ubuntu2.4 [116 kB]
Fetched 116 kB in 4s (32.5 kB/s)
Preconfiguring packages ...
Selecting previously unselected package isc-dhcp-relay.
(Reading database ... 75287 files and directories currently installed.)
Preparing to unpack .../isc-dhcp-relay_4.4.1-2.3ubuntu2.4_amd64.deb ...
Unpacking isc-dhcp-relay (4.4.1-2.3ubuntu2.4) ...
Setting up isc-dhcp-relay (4.4.1-2.3ubuntu2.4) ...
Generating /etc/default/isc-dhcp-relay...
Created symlink /etc/systemd/system/multi-user.target.wants/isc-dhcp-relay.service → /lib/systemd/system/isc-dhcp-relay.service.
Created symlink /etc/systemd/system/multi-user.target.wants/isc-dhcp-relay6.service → /lib/systemd/system/isc-dhcp-relay6.service.
Processing triggers for man-db (2.10.2-1) ...
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