centos 7 上配置dnsmasq 同时支持ipv4和ipv6的DHCP服务

xiaoxiao2025-03-31 10

dnsmasq版本： dnsmasq 从2.6*版本开始支持DHCPv6功能

参考：https://blog.csdn.net/qq_35550345/article/details/86628962

dhcpv6原理：https://blog.csdn.net/qq_38265137/article/details/80466734

ifcfg配置参数介绍：https://blog.csdn.net/chinaltx/article/details/86497165

一、不指定分配地址

dnsmasq服务器配置dnsmasq服务器ipv6地址（本测试接口为eth0） /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 TYPE=Ethernet ONBOOT=yes NM_CONTROLLED=no BOOTPROTO=dhcp DEFROUTE=yes IPV4_FAILURE_FATAL=yes PEERDNS=yes IPV6INIT=yes IPV6to4INIT=yes IPV6FORDING=yes IPV6ADDR=fd00::1/64

/etc/sysconfig/network

NETWORKING_IPV6=yes

设置dnsmasq.conf read-ethers log-dhcp log-queries log-facility=/var/log/dnsmasq.log addn-hosts = /var/lib/cobbler/cobbler_hosts domain=local dhcp-lease-max=1800 server=/local/ resolv-file=/etc/dnsmasq.upstream interface=eth0 cache-size=1024 # This is one of the key options. dnsmasq tries to move out servername # and PXE filename from special fields into DHCP options. # Some old clients can't understand those DHCP options, so they # will not be able to boot via PXE without this option enabled. # For example gPXE will not work while iPXE works fine. dhcp-no-override # for many simultaneously DHCPDISCOVVER requests dnsmasq can offer # the same IP for two differnt MAC addresses. This option prevents it # by assigning IPs one by one instead of using hash algorithm. dhcp-sequential-ip #ipv4 dhcp-option=6,10.10.1.2 dhcp-range=internal,10.10.1.128,10.10.1.254,255.255.255.0,120m dhcp-option=net:internal,option:router,10.10.1.2 dhcp-boot=net:internal,pxelinux.0,boothost,10.10.1.2 #ipv6 dhcp-range=fd00::22, fd00::44, 64, 1h enable-ra #domain-needed #resolv-file=/etc/resolv.dnsmasq.conf

检查语法并启动dnsmasq：dnsmasq -test

杀掉测试进程后启动dnsmasq & dhcp租用信息：/var/lib/dnsmasq/dnsmasq.leases

客户端配置网卡配置客户机上的接口为eth0，网卡配置文件/etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 ONBOOT=yes #禁止NetworkManager管理网卡 NM_CONTROLLED=no HWADDR= #USERCTL=no PEERDNS=yes BOOTPROTO=dhcp #只能小写 #BOOTPROTO=dhcp6 打开这个只会获取ipv6的地址 DHCPV6C=yes IPV6INIT=yes

网络配置文件/etc/sysconfig/network NETWORKING_IPV6=yes IPV6_AUTOCONF=yes #yes表示自动获取地址

测试： dhclient -6 -v eth0

二、指定分配地址

使用dnsmasq 有状态DHCPv6下发特定租约

上面的方式是dnsmasq按照特定算法给客户端分配ipv4和ipv6地址，如果想给每个客户端分配指定地址，需要增加以下配置。

dnsmasq服务器（dnsmasq.conf ）配置和上面一样，添加以下语句 dhcp-host=id:00:03:01:00:08:00:27:5c:b9:f0, [fd00::22]

修改配置需要重启dnsmasq服务

客户端

根据官方描述，dhclient版本为4.1+支持ipv6。为了支持DUID-LL要在/etc/dhcp/dhclient.conf中写入：

ZQ send dhcp6.client-id = concat(00:03:00, hardware); /etc/sysconfig/network-scripts/ifcfg-eth0跟上面一样配置/etc/sysconfig/network

NETWORKING_IPV6=yes IPV6_AUTOCONF=no

客户端租约文件/var/lib/dhclient/dhclient6.leases

三、问题分析

centos7使用NetworkManager启动dhclient （NM_CONTROLLED=yes ）