Nginx+keepalived双机热备

一：环境介绍:

Nginx Master: 122.112.X.XNginx Backup: 211.101.X.XVIP:Keepalived 1.2.13Nginx安装见nginx安装配置文档Master与Backup的Nginx配置一致.在MASTER跟BACKUP上安装Keepalived:

二：安 装：\\ 两台接入服务器分别安装NginX和keepalived:

#tar zxvf keepalived-1.2.13.tar.gz   #cd /usr/local/keepalived-1.2.13 #./configure  && make && make install       Keepalived configuration      ------------------------      Keepalived version       : 1.2.13      Compiler                 : gcc      Compiler flags           : -g -O2      Extra Lib                : -lssl -lcrypto -lcrypt       Use IPVS Framework       : Yes      IPVS sync daemon support : Yes      IPVS use libnl           : No      fwmark socket support    : Yes      Use VRRP Framework       : Yes      Use VRRP VMAC            : Yes      SNMP support             : No      SHA1 support             : No      Use Debug flags          : No       （ 出现以上提示则安装成功 ）       #cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/#cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/#mkdir /etc/keepalived#cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/#cp /usr/local/sbin/keepalived /usr/sbin/ #service keepalived start|stop                         #做成系统启动服务方便管理.  #echo "/etc/init.d/keepalived start" >> /etc/rc.local        #加入启动服务

三：配置：\\修改MASTER 的keepalived.conf

#vim /etc/keepalived/keepalived.conf  

! Configuration File for keepalived

global_defs {   notification_email {     [email protected]     [email protected]     [email protected]   }   notification_email_from [email protected]   smtp_server 192.168.200.1   smtp_connect_timeout 30   router_id nginx_master}vrrp_script chk_http_port {                 script "/usr/local/scripts/nginx_pid.sh" ###监控脚本          interval 2 ###监控时间          weight 2          }  vrrp_instance VI_1 {          state MASTER ### 设置为主          interface eth0 ### 监控网卡          virtual_router_id 51 ### 这个两台服务器必须一样          priority 101 ### 权重值MASTRE一定要高于BAUCKUP          authentication {          auth_type PASS ### 加密          auth_pass test ### 加密的密码，两台服务器一定要一样，不然会出错          }          track_script {          chk_http_port ### 执行监控的服务          }          virtual_ipaddress {                          192.168.128.177 ### VIP 地址                  }  }  

\\修改BACKUP keepalived.conf

#vim /etc/keepalived/keepalived.conf  

! Configuration File for keepalived

global_defs {   notification_email {     [email protected]     [email protected]     [email protected]   }   notification_email_from [email protected]   smtp_server 192.168.200.1   smtp_connect_timeout 30   router_id nginx_backup}vrrp_script chk_http_port {          script "/opt/nginx_pid.sh"          interval 2          weight 2  }  vrrp_instance VI_1 {          state BACKUP ### 设置为备份机          interface eth0          virtual_router_id 51 ### 与 MASTRE 设置值一样          priority 80 ### 比 MASTRE权重值低            authentication {          auth_type PASS          auth_pass test ### 密码 与 MASTRE 一样          }          track_script {          chk_http_port          }          virtual_ipaddress {          192.168.128.177          }  }  

\\编写监控nginx监控脚本

#vim /usr/local/scripts/nginx_pid.sh 

 #!/bin/bash  A=`ps -C nginx --no-header |wc -l` ## 查看是否有 nginx进程 把值赋给变量A  if [ $A -eq 0 ];then <span style="white-space:pre"> </span>## 如果没有进程值得为 零  <span style="white-space:pre">  </span>/usr/local/nginx/sbin/nginx  <span style="white-space:pre">  </span>sleep 3  <span style="white-space:pre">  </span>if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then  <span style="white-space:pre">  </span>killall keepalived ## 则结束 keepalived 进程  <span style="white-space:pre">  </span>fi  fi  

\\测试,分别在两个服务器 启动 nginx 和 keepalived

1>先后在主、从服务器上启动keepalived: /etc/init.d/keepalived start2>在主服务器上查看是否已经绑定了虚拟IP： ip addr3>停止主服务器上的keepalived: /etc/init.d/keepalived stop 然后在从服务器上查看是否已经绑定了虚拟IP：4>启动主服务器上的keepalived，看看主服务器能否重新接管虚拟IP\\监控 Nginx Mastaer 的日志

May 12 17:33:44 localhost Keepalived_vrrp: Configuration is using : 35676 Bytes  May 12 17:33:44 localhost Keepalived: Starting VRRP child process, pid=1245  May 12 17:33:44 localhost Keepalived_vrrp: VRRP sockpool: [ifindex(2), proto(112), fd(8,9)] May 12 17:33:45 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Transition to MASTER STATE  May 12 17:33:46 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering MASTER STATE  May 12 17:33:46 localhost Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.  May 12 17:33:46 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.128.177  May 12 17:33:46 localhost avahi-daemon[2344]: Registering new address record for 192.168.128.177 on eth0.  May 12 17:33:46 localhost Keepalived_vrrp: Netlink reflector reports IP 192.168.128.177 added  

\\监控 Nginx Backup 的日志

May 11 22:28:21 localhost Keepalived: Starting Keepalived v1.1.15 (05/11,2010)  May 11 22:28:21 localhost Keepalived_vrrp: Using MII-BMSR NIC polling thread...  May 11 22:28:21 localhost Keepalived_vrrp: Registering Kernel netlink reflector  May 11 22:28:21 localhost Keepalived_vrrp: Registering Kernel netlink command channel  May 11 22:28:21 localhost Keepalived_vrrp: Registering gratutious ARP shared channel  May 11 22:28:21 localhost Keepalived: Starting VRRP child process, pid=27040  May 11 22:28:21 localhost Keepalived_vrrp: Opening file ‘/etc/keepalived/keepalived.conf‘.  May 11 22:28:21 localhost Keepalived_vrrp: Configuration is using : 35538 Bytes  May 11 22:28:21 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering BACKUP STATE  May 11 22:28:21 localhost Keepalived_vrrp: VRRP sockpool: [ifindex(2), proto(112), fd(7,8)]  May 11 22:28:23 localhost Keepalived_vrrp: VRRP_Script(chk_http_port) succeeded  看日志可以看出，两台服务器的 MASTRE 和 BACUKUP 已经都正常了

现在我们把Master的Nginx停掉.查看Backup的日志

[plain] view plaincopyMay 11 22:28:21 localhost Keepalived: Starting VRRP child process, pid=27040  May 11 22:28:21 localhost Keepalived_vrrp: Opening file ‘/etc/keepalived/keepalived.conf‘.  May 11 22:28:21 localhost Keepalived_vrrp: Configuration is using : 35538 Bytes  May 11 22:28:21 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering BACKUP STATE  May 11 22:28:21 localhost Keepalived_vrrp: VRRP sockpool: [ifindex(2), proto(112), fd(7,8)]  May 11 22:28:23 localhost Keepalived_vrrp: VRRP_Script(chk_http_port) succeeded  May 11 22:29:25 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Transition to MASTER STATE  May 11 22:29:26 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering MASTER STATE  May 11 22:29:26 localhost Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.  May 11 22:29:26 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.128.177  可以看出backup已经变成master

现在再启动原来master的nginx,再查看backup的日志

[plain] view plaincopyMay 11 22:30:32 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Received higher prio advert  May 11 22:30:32 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering BACKUP STATE  May 11 22:30:32 localhost Keepalived_vrrp: VRRP_Instance(VI_1) removing protocol VIPs.  May 11 22:30:32 localhost avahi-daemon[2409]: Withdrawing address record for 192.168.128.177 on eth0.  可以看出又变回了backup.