Keepalived + Nginx + Tomcat 的高可用负载均衡架构搭建详解架构师

jdk-8u151-linux-x64.rpm 
apache-tomcat-7.0.52.tar.gz 
http://nginx.org/download/nginx-1.12.2.tar.gz 
http://www.keepalived.org/software/keepalived-1.3.2.tar.gz

服务器准备和规划: 
         IP地址               部署服务                                  主从关系 
         192.168.153.128     Nginx+keepalived                         Maser 
         192.168.153.129     Nginx+keepalived                         Slave 
         192.168.153.130     Java1.8+tomcat7[8080+ tomcat8090]          - 

[[email protected] opt]# tar -zxvf nginx-1.12.2.tar.gz 
[[email protected] opt]# cd nginx-1.12.2 
[[email protected] nginx-1.12.2]# ./configure --prefix=/usr/local/nginx --with-http_stub_status_module --with-http_ssl_module 
[[email protected] nginx-1.12.2]# make && make install

[[email protected] opt]# tar -zxvf keepalived-1.3.2.tar.gz  
[[email protected] opt]# cd keepalived-1.3.2/ 
[[email protected] keepalived-1.3.2]# ./configure --prefix=/usr/local/keepalived --sysconf=/etc/ 
[[email protected] keepalived-1.3.2]# make && make install

worker_processes  1; 
events { 
    worker_connections  1024; 
} 
http { 
    include       mime.types; 
    default_type  application/octet-stream; 
    sendfile        on; 
    keepalive_timeout  65; 
 
     
    server { 
        listen       80; 
        server_name  localhost; 
 
        location / { 
            root   html; 
            index  index.html index.htm; 
            proxy_connect_timeout 3; 
            proxy_send_timeout 30; 
            proxy_read_timeout 30; 
            proxy_pass http://localhost; 
        } 
  
        error_page   500 502 503 504  /50x.html; 
        location = /50x.html { 
            root   html; 
        } 
    } 
    upstream localhost { 
       server 192.168.153.130:8080 weight=2; 
       #server 192.168.153.130:8090 weight=2; 
    } 
 
}

#! Configuration File for keepalived 
#全局配置 
global_defs { 
   #keepalived切换的时候，发消息到指定的email，可配置多个email 
   notification_email { 
     [email protected] 
   } 
    
   #通知邮件从哪个地址发出 
   notification_email_from [email protected] 
   #通知邮件的smtp地址 
   smtp_server smtp.exmail.qq.com 
   #连接smtp服务器的超时时间，单位秒 
   smtp_connect_timeout 30 
   #Keepalived的机器标识，一个网络内保持唯一 
   router_id nginx-master 
} 
#执行脚本配置 
vrrp_script chk_nginx { 
#脚本所在路径 
    script "/usr/local/keepalived/etc/check_nginx.sh" 
#脚本执行间隔时间，秒 
    interval 2 
#优先级 
    weight 2 
} 
#keepalived实例配置 
 
vrrp_instance VI_1 { 
#指定实例的初始状态，MASTER或BACKUP两种状态，并且需要大写 
    state MASTER 
#实例绑定的网卡 
    interface eth0 
#虚拟路由标识，是一个数字，整个VRRP内唯一，如果keepalived配置了主备，需要相同 
    virtual_router_id 51 
#优先级，数值愈大，优先级越高 
    priority 100 
#MASTER与BACKUP之间同步检查的时间间隔，单位为秒 
    advert_int 1 
#通信验证 
    authentication { 
        auth_type PASS 
        auth_pass 123456 
    }     
#追踪外围脚本 
    track_script { 
    #这里配置vrrp_script的名称 
        chk_nginx 
    }     
     
#虚拟ip配置，可配置多个 
    virtual_ipaddress { 
        192.168.153.200 
    } 
}

vim /usr/local/keepalived/etc/check_nginx.sh 
#!/bin/sh 
NGINX=/usr/local/nginx/sbin/nginx 
PORT=80 
nmap localhost -p $PORT | grep "$PORT/tcp open" 
#echo $? 
if [ $? -ne 0 ];then 
    $NGINX -s stop 
    #这里再次尝试启动NG 
    $NGINX 
    sleep 5 
    nmap localhost -p $PORT | grep "$PORT/tcp open" 
    [ $? -ne 0 ] && cd /usr/local/keepalived/sbin && pkill keepalived 
    echo "stoped" 
fi

[[email protected] ~]#ln -s /usr/local/keepalived/sbin/keepalived /sbin/ 
[[email protected] ~]# keepalived -D -f /etc/keepalived/keepalived.conf 
[[email protected] ~]#tail -100f /var/log/messages