Nginx（负载均衡）+keepalived（双机热备)

实验场景:



负载均衡:
LB主:192.168.1.1

LB从;192.168.1.2

VIP:192.168.1.3

web服务器:
web1:192.168.1.4

web2:192.168.1.5

一，      安装nginx依赖: 查看是否已经安装
 rpm -qa |grep gcc  openssl-devel pcre-devel  zlib-devel

二，    分别在主从服务器上安装nginx

#tar -zxf nginx-1.1.2.tar.gz

#./configure

#make &&　make install
修改# vim /usr/local/nginx/conf/nginx.conf
worker_processes  32; (32是你物理机内存的二倍)
在http {  } 里添加

         upstreammyserver{

         server 192.168.1.4;  //web1服务器地址

         server 192.168.1.5; //web2服务器地址

}

    server {

                listen      80;

                server_name  myserver;

                #charset koi8-r;

                #access_log  logs/host.access.log  main;

  location / {

              proxy_passhttp://myserver;

               proxy_next_upstream http_500 http_503error timeout invalid_header;

               include /usr/local/nginx/conf/proxy.conf;（这个文件要自己创建）

                #root  html;

                #index index.html index.htm;

        }

 

创建 touch /usr/local/nginx/conf/proxy.conf
[root@localhost conf]# cat   proxy.conf

proxy_redirect off;

proxy_set_header Host $host;

proxy_set_header X-Real-IP $remote_addr;

proxy_set_header X-Forwarded-For$proxy_add_x_forwarded_for;

client_body_buffer_size 128k;

proxy_connect_timeout 90;

proxy_send_timeout 90;

proxy_read_timeout 90;

proxy_buffer_size 4k;

proxy_buffers 4 32k;

proxy_busy_buffers_size 64k;

proxy_temp_file_write_size 64k;

三、验证效果

            判断配置文件是否正确　

#/usr/local/nginx/sbin/nginx -t -c /usr/local/nginx/conf/nginx.conf

nginx: theconfiguration file /usr/local/nginx/conf/nginx.conf syntax is ok

nginx:configuration file /usr/local/nginx/conf/nginx.conf test is successful

更改配置重启nginx

kill -HUP 主进程号或进程号文件路径

或者使用

cd /usr/local/nginx/sbin

./nginx -s reload

          分别在两台web服务器上安装nginx

Web1服务器上 echo service1 > /usr/local/nginx/html/index.html

Web2服务器上echo web2 > /usr/local/nginx/html/index.html



四 、问题总结：

问题 :  [error] 33249#0: *46 no live upstreams whileconnecting to upstream, client: 10.16.21.118, server: myserver, request:"GET /favicon.ico HTTP/1.1", upstream: "http://myserver/favicon.ico",host: "10.16.21.20", referrer: "http://10.16.21.20/"
解决方法

1.  查看nginx错误日志，检查nginx.conf 配置文件中配置是否正确

2. Iptables –L关闭防火墙  setenforce 0

分别在主从服务器上安装keepalive

//本文参照http://www.open-open.com/lib/view/open1453698551808.html

#tar -zxvfkeepalived-1.2.7.tar.gz

# yum -y install kernel-headers kernel-devel 

#./configure  --prefix=/usr/local/keepalived --sysconfdir=/etc/

--with-kernel-dir=/usr/src/kernels/2.6.32-573.12.1.el6.x86_64

#make && make install
#ln -s /usr/local/sbin/keepalived /sbin/

#chkconfig keepalived on

#vim /etc/keepalived/keepalived.conf (将原来的配置文件备份后修改)

1. global_defs {  

2.     router_id Nod
a7e4
eB  
3. }  

4. vrrp_instance VI_1 {  
5.     state Master    #设置为主服务器  

6.     interface eth0  #监测网络接口  
7.     virtual_router_id 51  #主、备必须一样  

8.     priority 90   #(主、备机取不同的优先级，主机值较大，备份机值较小,值越大优先级越高)  
9.     advert_int 1   #VRRP Multicast广播周期秒数  

10.    authentication {  
11.     auth_type PASS  #VRRP认证方式，主备必须一致  

12.    auth_pass 1111   #(密码)  
13. }  

14.virtual_ipaddress {  
15.     192.168.1.3/24  #VRRP HA虚拟地址  

16.}  

启动keepalived服务

# service keepalived start 或者keepalived -D -f/usr/local/etc/keepalived/keepalived.conf

#ip a

eth0:<BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen1000

   link/ether 00:0c:29:a8:ff:bb brd ff:ff:ff:ff:ff:ff

   inet 192.168.1.1/24 brd 10.16.21.255 scope global eth0

   inet 192.168.1.3/24 scope global secondary eth0    ///vip地址

   inet6 fe80::20c:29ff:fea8:ffbb/64 scope link

      valid_lft forever preferred_lft forever