keepalived+nginx双机热备+负载均衡

 2018-07-11 15:25   796
keepalived+nginx双机热备+负载均衡

最近因业务扩展，需要将当前的apache 转为nginx(web), 再在web前端放置nginx(负载均衡)。同时结合keepalived 对前端nginx实现HA。
nginx进程基于于Master+Slave(worker)多进程模型，自身具有非常稳定的子进程管理功能。在Master进程分配模式下，Master进程永远不进行业务处理，只是进行任务分发，从而达到Master进程的存活高可靠性，Slave(worker)进程所有的业务信号都 由主进程发出，Slave(worker)进程所有的超时任务都会被Master中止，属于非阻塞式任务模型。
Keepalived是Linux下面实现VRRP 备份路由的高可靠性运行件。基于Keepalived设计的服务模式能够真正做到主服务器和备份服务器故障时IP瞬间无缝交接。二者结合，可以构架出比较稳定的软件lb方案。




准备4台电脑来做这个实验:

192.168.232.132        web服务器
192.168.232.133        web服务器
192.168.232.134        keepalived nginx
192.168.232.135        keepalived nginx

虚拟IP (VIP)：192.168.232.16

134\135两个主机配置虚拟IP


下面以135为例：

vi /etc/sysconfig/network-scripts/ifcfg-eth2:0


		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						DEVICE=eth2:0
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						TYPE=Ethernet
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						ONBOOT=yes
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						BOOTPROTO=static
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						DNS1=192.168.232.2
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						IPADDR=192.168.232.16
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						NETMASK=255.255.255.0
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						GETWAY=192.168.232.2
					
    

				
    

			
    9.



service network restart

使用ifconfig查看效果：

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						eth2      Link encap:Ethernet  HWaddr 00:0C:29:49:90:5B
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						inet addr:192.168.232.135 Bcast:192.168.232.255 Mask:255.255.255.0
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						inet6 addr: fe80::20c:29ff:fe49:905b/64 Scope:Link
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						UP BROADCAST RUNNING MULTICAST  MTU:1500 Metric:1
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						RX packets:66322 errors:0 dropped:0 overruns:0 frame:0
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						TX packets:31860 errors:0 dropped:0 overruns:0 carrier:0
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						collisions:0 txqueuelen:1000
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						RX bytes:67624991 (64.4 MiB)  TX bytes:2723877 (2.5 MiB)
					
    

				
    

			
    9. 

			
  9. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Interrupt:19 Base address:0x2000
					
    

				
    

			
    10. 

			
  10. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    11. 

			
  11. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						eth2:0 Link encap:Ethernet  HWaddr 00:0C:29:49:90:5B
					
    

				
    

			
    12. 

			
  12. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						inet addr:192.168.232.16 Bcast:192.168.232.255 Mask:255.255.255.0
					
    

				
    

			
    13. 

			
  13. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						UP BROADCAST RUNNING MULTICAST  MTU:1500 Metric:1
					
    

				
    

			
    14. 

			
  14. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Interrupt:19 Base address:0x2000
					
    

				
    

			
    15. 

			
  15. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    16. 

			
  16. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						lo        Link encap:Local Loopback
					
    

				
    

			
    17. 

			
  17. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						inet addr:127.0.0.1 Mask:255.0.0.0
					
    

				
    

			
    18. 

			
  18. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						inet6 addr: ::1/128 Scope:Host
					
    

				
    

			
    19. 

			
  19. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						UP LOOPBACK RUNNING  MTU:16436 Metric:1
					
    

				
    

			
    20. 

			
  20. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						RX packets:22622 errors:0 dropped:0 overruns:0 frame:0
					
    

				
    

			
    21. 

			
  21. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						TX packets:22622 errors:0 dropped:0 overruns:0 carrier:0
					
    

				
    

			
    22. 

			
  22. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						collisions:0 txqueuelen:0
					
    

				
    

			
    23. 

			
  23. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						RX bytes:1236328 (1.1 MiB)  TX bytes:1236328 (1.1 MiB)
					
    

				
    

			
    24.


          
说明生效了。

134\135两个主机安装keepalived和nginx


nginx安装：

1、导入外部软件库
rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/6/i386/epel-release-6-5.noarch.rpm
rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/6/i386/ius-release-1.0-10.ius.el6.noarch.rpm
rpm -Uvh http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6-0.el6.ngx.noarch.rpm
以下添加注释
mirrorlist=http://dmirr.iuscommunity.org/mirrorlist?repo=ius-el6&arch=$basearch
以下删除注释
#baseurl=http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/$basearch
2、yum安装nginx
yum install nginx

keepalived安装：

安装依赖
yum -y install gcc gcc+ gcc-c++
yum install popt-devel openssl openssl-devel libssl-dev libnl-devel popt-devel

安装内核
yum -y install kernel kernel-devel
当前kernel代码建立连接 ln -s /usr/src/kerners/2.6....../ /usr/src/linux

安装keepalived
wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
tar -zxvf keepalived-1.2.2.tar.gz  
cd keepalived-1.2.2  
./configure  
make  
make install   

拷贝相应的文件

cp /usr/local/sbin/keepalived /usr/sbin/ 
cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/  
cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/  
cp -r /usr/local/etc/keepalived/ /etc/  

配置keeplived和nginx主机


134/135执行都执行以下操作：
vi /etc/nginx/conf.d/default.conf

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						server {
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						listen 8088;
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						server_name  localhost;
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						location / {
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						root   /var/www/html;
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						index index.html index.htm;
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    9. 

			
  9. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    10. 

			
  10. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						error_page 500 502 503 504 /50x.html;
					
    

				
    

			
    11. 

			
  11. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						location = /50x.html {
					
    

				
    

			
    12. 

			
  12. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						 root   /usr/share/nginx/html;
					
    

				
    

			
    13. 

			
  13. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						 }
					
    

				
    

			
    14. 

			
  14. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    15.

135执行以下操作：
vi /var/www/html/index.html

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<html>
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<head>
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<title>Welcome to nginx!</title> 
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</head>
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<body bgcolor="white" text="black">
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<center><h1>Welcome to nginx! 192.168.232.135</h1></center>
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</body> 
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</html>
					
    

				
    

			
    9.

134执行以下操作：
vi /var/www/html/index.html

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<html>
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<head>
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<title>Welcome to nginx!</title> 
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</head>
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<body bgcolor="white" text="black">
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						<center><h1>Welcome to nginx! 192.168.232.134</h1></center>
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</body> 
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						</html>
					
    

				
    

			
    9.

134执行以下操作：
vi /etc/keepalived/keepalived.conf

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						! Configuration File for keepalived
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						global_defs {
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						notification_email {
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#acassen@firewall.loc
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#failover@firewall.loc
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#sysadmin@firewall.loc
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    9. 

			
  9. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#notification_email_from Alexandre.Cassen@firewall.loc
					
    

				
    

			
    10. 

			
  10. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#smtp_server 192.168.200.1
					
    

				
    

			
    11. 

			
  11. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#smtp_connect_timeout 30
					
    

				
    

			
    12. 

			
  12. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						router_id LVS_DEVEL
					
    

				
    

			
    13. 

			
  13. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    14. 

			
  14. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    15. 

			
  15. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						vrrp_script chk_http_port {
					
    

				
    

			
    16. 

			
  16. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						script "</dev/tcp/127.0.0.1/8088"
					
    

				
    

			
    17. 

			
  17. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						interval 1
					
    

				
    

			
    18. 

			
  18. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						weight -2
					
    

				
    

			
    19. 

			
  19. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    20. 

			
  20. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    21. 

			
  21. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						vrrp_instance VI_1 {
					
    

				
    

			
    22. 

			
  22. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						state MASTER
					
    

				
    

			
    23. 

			
  23. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						interface eth2
					
    

				
    

			
    24. 

			
  24. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						virtual_router_id 51
					
    

				
    

			
    25. 

			
  25. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						priority 100
					
    

				
    

			
    26. 

			
  26. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						advert_int 1
					
    

				
    

			
    27. 

			
  27. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						authentication {
					
    

				
    

			
    28. 

			
  28. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						auth_type PASS
					
    

				
    

			
    29. 

			
  29. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						auth_pass 1111
					
    

				
    

			
    30. 

			
  30. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    31. 

			
  31. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						virtual_ipaddress {
					
    

				
    

			
    32. 

			
  32. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						192.168.232.16
					
    

				
    

			
    33. 

			
  33. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    34. 

			
  34. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						track_script {
					
    

				
    

			
    35. 

			
  35. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						chk_http_port
					
    

				
    

			
    36. 

			
  36. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    37. 

			
  37. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    38.

135执行以下操作：
vi /etc/keepalived/keepalived.conf

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						! Configuration File for keepalived
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						global_defs {
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						notification_email {
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#acassen@firewall.loc
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#failover@firewall.loc
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#sysadmin@firewall.loc
					
    

				
    

			
    8. 

			
  8. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    9. 

			
  9. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#notification_email_from Alexandre.Cassen@firewall.loc
					
    

				
    

			
    10. 

			
  10. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#smtp_server 192.168.200.1
					
    

				
    

			
    11. 

			
  11. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						#smtp_connect_timeout 30
					
    

				
    

			
    12. 

			
  12. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						router_id LVS_DEVEL
					
    

				
    

			
    13. 

			
  13. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    14. 

			
  14. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    15. 

			
  15. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						vrrp_script chk_http_port {
					
    

				
    

			
    16. 

			
  16. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						script "</dev/tcp/127.0.0.1/8088"
					
    

				
    

			
    17. 

			
  17. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						interval 1
					
    

				
    

			
    18. 

			
  18. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						weight -2
					
    

				
    

			
    19. 

			
  19. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    20. 

			
  20. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						
					
    

				
    

			
    21. 

			
  21. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						vrrp_instance VI_1 {
					
    

				
    

			
    22. 

			
  22. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						state BACKUP
					
    

				
    

			
    23. 

			
  23. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						interface eth2
					
    

				
    

			
    24. 

			
  24. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						virtual_router_id 51
					
    

				
    

			
    25. 

			
  25. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						priority 99
					
    

				
    

			
    26. 

			
  26. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						advert_int 1
					
    

				
    

			
    27. 

			
  27. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						authentication {
					
    

				
    

			
    28. 

			
  28. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						auth_type PASS
					
    

				
    

			
    29. 

			
  29. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						auth_pass 1111
					
    

				
    

			
    30. 

			
  30. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    31. 

			
  31. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						virtual_ipaddress {
					
    

				
    

			
    32. 

			
  32. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						192.168.232.16
					
    

				
    

			
    33. 

			
  33. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    34. 

			
  34. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						track_script {
					
    

				
    

			
    35. 

			
  35. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						chk_http_port
					
    

				
    

			
    36. 

			
  36. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    37. 

			
  37. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						}
					
    

				
    

			
    38.

Tips：

state   参数值：主的是MASTER、备用的是BACKUP
priority 参数值： MASTER > BACKUP
virtual_router_id： 参数值要一样

测试测试：


两台测试机134\135均启动keepalived和nginx
service keepalived restart
service keepalived nginx

验证nginx启动正常：
访问 master：http://192.168.232.134:8088/
访问 backup: http://192.168.232.135:8088/

查看keepalived的日志信息：

134\135均打开日志信息方便查看keepalived动态：
tail -f /var/log/messages

浏览器打开虚拟ip访问：http://192.168.232.16:8080/ ，此时显示IP为192.168.232.134

服务器层的双机热备（比如服务器宕机、keepalived宕了）测试：


kill 192.168.232.134（master) 的keepalived进程
killall keepalived
134的日志信息如下：

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 18:03:10 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth1 for 192.168.232.16
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 18:03:15 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth1 for 192.168.232.16
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:44 localhost Keepalived: Terminating on signal
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:44 localhost Keepalived: Stopping Keepalived v1.2.2 (06/10,2014)
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:44 localhost Keepalived_vrrp: Terminating VRRP child process on signal
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:44 localhost Keepalived_healthcheckers: Terminating Healthchecker child process on signal
					
    

				
    

			
    7.


135的日志信息如下：

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:50 localhost Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:50 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth2 for 192.168.232.16
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:50 localhost Keepalived_healthcheckers: Netlink reflector reports IP 192.168.232.16 added
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:30:55 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth2 for 192.168.232.16
					
    

				
    

			
    5.



刷新http://192.168.232.16:8080/ ， 此时显示IP为192.168.232.135。

再次启动192.168.232.134的keepalived进程，192.168.232.134会自动接管成为master，192.168.232.135自动转为backup，从测试结果看，备机能成功接管，已经实现了热备。

应用层（web）的双机热备（比如nginx进程被意外kill、web端口不通）试验：


关闭192.168.232.134（master) 的nginx服务：
service nginx stop

134的日志信息如下：

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:49 localhost Keepalived_vrrp: VRRP_Script(chk_http_port) failed
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:51 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Received higher prio advert
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:51 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering BACKUP STATE
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:51 localhost Keepalived_vrrp: VRRP_Instance(VI_1) removing protocol VIPs.
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:51 localhost Keepalived_healthcheckers: Netlink reflector reports IP 192.168.232.16 removed
					
    

				
    

			
    6.

135的日志信息如下：

		
    
			
			
  1. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:52 localhost Keepalived_vrrp: VRRP_Instance(VI_1) forcing a new MASTER election
					
    

				
    

			
    2. 

			
  2. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:53 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Transition to MASTER STATE
					
    

				
    

			
    3. 

			
  3. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:54 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering MASTER STATE
					
    

				
    

			
    4. 

			
  4. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:54 localhost Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.
					
    

				
    

			
    5. 

			
  5. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:54 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth2 for 192.168.232.16
					
    

				
    

			
    6. 

			
  6. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:54 localhost Keepalived_healthcheckers: Netlink reflector reports IP 192.168.232.16 added
					
    

				
    

			
    7. 

			
  7. 
				
				
    
					
					
    
						
					
    

				
    

				
    
					
					
    
						Jun 11 19:38:59 localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth2 for 192.168.232.16
					
    

				
    

			
    8.


刷新http://192.168.232.16:8080/ ， 此时显示IP为192.168.232.135。

再次启动192.168.232.134的nginx进程，192.168.232.134会自动接管成为master，192.168.232.135自动转为backup，从测试结果看，备机能成功接管，已经实现了热备。

为什么主备的参数state都是MASTER，对的你没有看错确实要都设置成一样的，不然并不能实现我们想要的VIP漂浮的效果，我测试很久才发现的.state都设置成MASTER后，会根据priority的值大小竞争来决定谁是真正的MASTER，脚本检测也是在失败的时候会把权重减去相应的值，比如原来master（181）的priority=100，如果脚本检测到端口8088无法连接，就会priority-2=98，< S-B（150）的priority（99），此时 S-B（150） 将竞争成为master，这样就实现了web应用的热备。


如果以上实验都没有问题了，那么就该nginx负载均衡的配置了，配置修改参见如下：http://blog.csdn.net/e421083458/article/details/30086413

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