Nginx使用Keepalived部署web集群（高可用高性能负载均衡）实战案例

---node01
[root@node01 ~]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.5.10
   smtp_connect_timeout 30
   router_id LVS_DEVEL1
}
vrrp_script check_nginx_service {
   script "/etc/keepalived/check_web_server_keepalive.sh"
   #script "killall -0 nginx"
   interval 2
}

vrrp_instance VI_1 {
    state MASTER
    interface ens33
    virtual_router_id 51
    priority 200
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_script {
       check_nginx_service
    }
    virtual_ipaddress {
        192.168.5.100
    }
}

[root@node01 ~]# systemctl restart keepalived.service



---node02
! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.5.10
   smtp_connect_timeout 30
   router_id LVS_DEVEL2
}
vrrp_script check_nginx_service {
   script "/etc/keepalived/check_web_server_keepalive.sh"
   #script "killall -0 nginx"
   interval 2
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_script {
       check_nginx_service
    }
    virtual_ipaddress {
        192.168.5.100
    }
}

[root@node02 ~]# systemctl restart keepalived.service

---node01
[root@node01 ~]# mv /etc/nginx/conf.d/default.conf{,.bak}
[root@node01 ~]# vim /etc/nginx/conf.d/vhost.conf
upstream nginx_keepalived_webservers {
   server 192.168.5.13:80 weight=1;
   server 192.168.5.14:80 weight=1;
}

server{
    listen       80;
    server_name  wan.ngin_keepalived.org;
    location / {
       proxy_set_header X-Forwarded-For $remote_addr;
       proxy_pass http://nginx_keepalived_webservers;
      }   
}

[root@node01 ~]# systemctl restart nginx


node02
[root@node02 ~]# mv /etc/nginx/conf.d/default.conf{,.bak}
[root@node02 ~]# vim /etc/nginx/conf.d/vhost.conf
upstream nginx_keepalived_webservers {
   server 192.168.5.13:80 weight=1;
   server 192.168.5.14:80 weight=1;
}

server{
    listen       80;
    server_name  wan.ngin_keepalived.org;
    location / {
       proxy_set_header X-Forwarded-For $remote_addr;
       proxy_pass http://nginx_keepalived_webservers;
      }   
}

[root@node02 ~]# systemctl restart nginx

---node01
[root@node01 ~]# vim /etc/keepalived/check_web_server_keepalive.sh
#!/bin/bash

http_status=`ps -C nginx --no-header | wc -l`
if [ $http_status -eq 0 ];then
   systemctl start nginx
   sleep 3
   if [ `ps -C nginx --no-header | wc -l` -eq 0 ]
   then
       systemctl stop keepalived
   fi
fi


[root@node02 ~]# vim /etc/keepalived/check_web_server_keepalive.sh
#!/bin/bash

http_status=`ps -C nginx --no-header | wc -l`
if [ $http_status -eq 0 ];then
   systemctl start nginx
   sleep 3
   if [ `ps -C nginx --no-header | wc -l` -eq 0 ]
   then
       systemctl stop keepalived
   fi
fi

---node03
[root@node03 ~]# yum install nginx-1.18.0-1.el7.ngx.x86_64.rpm -y
[root@node03 ~]# echo "`hostname -I` web test page..." > /usr/share/nginx/html/index.html
[root@node03 ~]# systemctl enable --now nginx


----node04
[root@node04 ~]# yum install nginx-1.18.0-1.el7.ngx.x86_64.rpm -y
[root@node04 ~]# echo "`hostname -I` web test page..." > /usr/share/nginx/html/index.html
[root@node04 ~]# systemctl enable --now nginx

[root@node04 ~]# systemctl stop nginx
[root@node04 ~]# systemctl is-active nginx
inactive

[root@node04 ~]# systemctl start nginx
[root@node04 ~]# systemctl is-active nginx
active

[root@node01 ~]# systemctl stop keepalived.service

[root@node01 ~]# systemctl start keepalived.service