Linux下如何用dnsmasq做dns cache server配置

安装过程比较简单
yum -y install dnsmasq* wget http://www.keepalived.org/software/keepalived-1.2.9.tar.gztar zxvf keepalived-1.2.9.tar.gzcd keepalived-1.2.9./configure --prefix=/usr/local/keepalivedmake && make installmkdir /etc/keepalivedcp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/ln -s /usr/local/keepalived/sbin/keepalived /usr/sbin/chkconfig --add keepalivedchkconfig --level 35 keepalived on
keepalived的配置很简单，只需要配置一个vip可以在两台server之间飘来飘去就可以实现主备了
! configuration file for keepalived global_defs {  notification_email {   xxx@xxx.com  }  notification_email_from xxx@xxx.com  smtp_server 127.0.0.1  smtp_connect_timeout 30  router_id lvs_devel} vrrp_instance dnscache {  state master         // 另一台配置backup  interface eth1        // 在哪个接口上进行服务器状态检测  virtual_router_id 51  priority 180         // backup机器上配置100  advert_int 1         // 检查间隔，单位为秒  authentication {    auth_type pass    auth_pass 1234  }   virtual_ipaddress {       // vip设置，指定到内网网卡     192.168.100.99/24 dev eth1  }}
dnsmasq的配置也很简单
resolv-file=/etc/resolv.dnsmasq.confcache-size=1000conf-dir=/etc/dnsmasq.d

　　将dns地址写入到/etc/resolv.dnsmasq.conf文件中
echo "nameserver 8.8.8.8" > /etc/resolv.dnsmasq.conf
　　本机和局域网其它全部的服务器dns解析都用它
echo "nameserver 192.168.100.99" > /etc/resolv.conf
　　最后找一台局域网server验证一下，如果能解析就说明正常了.
nslookup www.google.cn 192.168.100.99
　　此方案只适合小型企业，规模少的情况下使用，解析量大的时候还是用bind最好。
下面是其它网友的补充：
复制代码 代码如下:

sudo pacman -s --needed dnsmasq
cd /etc
[admin@huangye etc]$ sudo cp -v dnsmasq.conf{,.orig}
`dnsmasq.conf' -> `dnsmasq.conf.orig'
[admin@huangye etc]$ sudo vim dnsmasq.conf


相比来说，dnsmasq的配置简单多了：

复制代码 代码如下:

resolv-file=/etc/dnsmasq.resolv.conf
addn-hosts=/etc/dnsmasq.hosts
local=/localnet/
no-dhcp-interface=eth0
conf-dir=/etc/dnsmasq.d

复制代码 代码如下:

[admin@huangye etc]$ sudo cp -v resolv.conf dnsmasq.resolv.conf
password:
`resolv.conf' -> `dnsmasq.resolv.conf'
sudo mkdir /etc/dnsmasq.d
sudo touch /etc/dnsmasq.hosts
sudo /etc/rc.d/dnsmasq start

最后，别忘记加入rc.conf daemons,注意要在network后面。
dnsmasq 可从额外的hosts文件读取条目，如可以这样添加正向解析：
echo "ip地址 域名" > /etc/dnsmasq.hosts
另外，重启dnsmasq可以用sighup（可以在修改hosts文件后，让配置生效）
killall -s sighup dnsmasq
查看服务状态：
netstat -tunl
tcp        0      0 0.0.0.0:53              0.0.0.0:*               listen
udp        0      0 0.0.0.0:53              0.0.0.0:*