nginx使用keepalived实现高可用

环境：

主：linux-node1  110.0.0.137 备：linux-node2  110.0.0.138   VIP: 110.0.0.120  

NGINX安装：

# rpm -ivh http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6-0.el6.ngx.noarch.rpm # yum install nginx  

1.安装keepalived

  <pre><code> # yum -y install kernel-devel make gcc openssl-devel  libnl* popt*

# yum install -y openssl openssl-devel

# wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz # tar zxf keepalived-1.2.2.tar.gz  # cd keepalived-1.2.2 # ./configure  --prefix=/usr/local/keepalived # make && make install # cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/ # cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/ /bin/cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/     # chmod +x /etc/init.d/keepalived # mkdir /etc/keepalived # /bin/cp /usr/local/sbin/keepalived /usr/sbin/ # ll /usr/sbin/   </code></pre>  

2.配置keepalived

2.1.配置主nginx（linux-node1）     [root@linux-node1 ~]# cat /etc/keepalived/keepalived.conf  ! Configuration File for keepalived   global_defs {    notification_email {      sysadmin@firewall.loc    }    notification_email_from Alexandre.Cassen@firewall.loc    smtp_server 127.0.0.1    smtp_connect_timeout 30    router_id LVS_DEVEL } vrrp_script chk_http_port { script "/opt/nginx_pid.sh" interval 2 weight 2 }   vrrp_instance VI_1 {     state MASTER     interface eth0     virtual_router_id 51     mcast_src_ip 110.0.0.137     priority 100     advert_int 1     authentication {         auth_type PASS         auth_pass 1111     }     track_script { chk_http_port     }     virtual_ipaddress {         110.0.0.120     } }   2.2.配置从nginx（linux-node2） [root@linux-node2 keepalived]# cat /etc/keepalived/keepalived.conf  ! Configuration File for keepalived   global_defs {    notification_email {      sysadmin@firewall.loc    }    notification_email_from Alexandre.Cassen@firewall.loc    smtp_server 127.0.0.1    smtp_connect_timeout 30    router_id LVS_DEVEL } vrrp_script chk_http_port { script "/opt/nginx_pid.sh" interval 2 weight 2 }   vrrp_instance VI_1 {     state BACKUP     interface eth0     virtual_router_id 51     mcast_src_ip 110.0.0.138     priority 99     advert_int 1     authentication {         auth_type PASS         auth_pass 1111     }     track_script { chk_http_port     }     virtual_ipaddress {         110.0.0.120     } }  

3.编写nginx检查脚本（主备都需要）：

  #!/bin/bash A=`ps -C nginx --no-header |wc -l` if [ $A -eq 0 ];then /etc/init.d/nginx start  sleep 3 if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then /etc/init.d/keepalived stop fi fi  

4.启动nginx和keepalived

/etc/init.d/nginx start /etc/init.d/keepalived start  

5.检查虚拟化IP 是否绑定成功

主节点： 可以看到vip 110.0.0.120 已经绑定到主的nginx服务器上了。  

6.测试：

停止nginx # /etc/init.d/nginx stop 发现主的nginx无法停止，因为/opt/nginx_pid.sh  会检查nginx状态，如果nginx停止了，那么这个脚本就会自动启动nginx。如果nginx启动失败，那么会立刻停止keepalived，把vip转移到backup  nginx上面   我们把nginx的配置文件设置错误，然后停止nginx，这个主的nginx就无法启动了。 检查主nginx机器ip状态：   检查backup nginx主机状态： 看到VIP已经转移到backup主机上了。    

来自为知笔记(Wiz)