lvs + keepalived + nginx + tomcat高可用负载反向代理服务器配置（二） LVS+Keepalived

一、安装ipvs

sudo apt-get install ipvsadm

二、安装keepalived

sudo apt-get install keepalived

三、创建keepalived.conf文件

sudo gedit /etc/keepalived/keepalived.conf

四、配置keepalived.conf

　　说明：VIP: 192.168.2.68

　　　　　real_server: 192.168.2.66(MASTER), 192.168.2.67(BACKUP)

# Global Configuration
global_defs {
    lvs_id  director1
}

# VRRP Configuration
vrrp_instance LVS {　　　　　　 #定义虚拟路由，LVS 为虚拟路由的标示符，自己定义名称
    state MASTER              #备份服务器上将MASTER改为BACKUP
    interface eth0
    virtual_router_id 51　　　 #虚拟路由的ID，而且这个ID也是虚拟MAC最后一段的来源，这个ID号一般不能大于255，且这个ID一定不能有冲突
    priority 150　　　　　　　　 #初始优先级
    advert_int 1　　　　　　　　 #通告的个数
    authentication {　　　　　　#认证机制
        auth_type PASS　　　　 #认证类型
        auth_pass 123456　　　 #密码，应该为随机的字符串
    }

    virtual_ipaddress {　　　　#虚拟地址，即VIP
        192.168.2.68
　　　　　#(如果有多个VIP，继续换行填写.) 
    }

    # Virtual Server Configuration - for WWW service
    virtual_server 192.168.2.68  {
        delay_loop 1                       #(每隔1秒查询realserver状态)
        lb_algo rr                         #(lvs 算法)
        lb_kind DR                         #(Direct Route)
        persistence_timeout 60             #(同一IP的连接60秒内被分配到同一台realserver)
        protocol TCP                       #(用TCP协议检查realserver状态) 

        # Real Server  configuration
        real_server 192.168.2.67  {
            weight 1                       #权重
            TCP_CHECK {
                connection_timeout 10      #(10秒无响应超时)
                nb_get_retry
                delay_before_retry
            }
        }

        # Real Server  configuration
        real_server 192.168.2.66  {
            weight
            TCP_CHECK {
                connection_timeout
                nb_get_retry
                delay_before_retry
            }
        }
    }
}

　　
　　1.配置vrrp   ip为68(启动keepalived之后可使用ip addr可查看)

　　

　　2.配置real_server   此处是67和66的一个集群

五、启动并查看keepalived

#service keepalived start
查看 keepalived状态
#  ps -ef | grep keepalived
root              : ?        :: keepalived -D
root           : ?        :: keepalived -D
root           : pts/    :: grep keepalived
如果未能启动，请使用sudo启动或者检查配置文件

# tail -f /var/log/syslog
Feb  :: localhost Keepalived_vrrp: Registering gratutious ARP shared channel
Feb  :: localhost Keepalived_vrrp: Opening file '/etc/keepalived/keepalived.conf'.
Feb  :: localhost Keepalived_vrrp: Configuration is using :  Bytes
Feb  :: localhost Keepalived_vrrp: Using LinkWatch kernel netlink reflector...
Feb  :: localhost Keepalived_vrrp: VRRP sockpool: [ifindex(), proto(), fd(,)]
Feb  :: localhost Keepalived_vrrp: VRRP_Instance(VI_1) Transition to MASTER STATE
Feb  :: localhost Keepalived_vrrp: VRRP_Instance(VI_1) Entering MASTER STATE
Feb  :: localhost Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.
Feb  :: localhost Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.2.68
Feb  :: localhost avahi-daemon[]: Registering new address record for 192.168.2.68 on eth0.

可以看到VIP已经在主服务器上开启

到此lvs+keepalived就已经完成了，接下来就是nginx.

Append: 使用Keepalived管理nginx

! Configuration File for keepalived

global_defs {
#   notification_email {
#        [e-mail]
#   }
#   notification_email_from [e-mail]
#   smtp_server 127.0.0.1
#   smtp_connect_timeout
    router_id LVS_DEVEL
}

vrrp_script chk_nginx {
   script "/etc/keepalived/check_nginx.sh"
   interval
   weight
}

vrrp_instance VI_1 {
    state BACKUP
    interface eno1
    virtual_router_id
    priority
    advert_int
    authentication {
        auth_type PASS
        auth_pass starhub
    }
    virtual_ipaddress {
        172.31.34.92
    }
    track_script {
        chk_nginx
   }
}

#virtual_server 172.31.34.92  {
#    delay_loop
#    lb_algo rr
#    lb_kind DR
#    nat_mask 255.255.255.248
#    persistence_timeout
#    protocol TCP
#    sorry_server 172.31.34.94
#    real_server 172.31.34.93  {
#        weight
#        notify_down /usr/local/bin/keepalived_notify.sh
#        TCP_CHECK {
#            connect_timeout
#            nb_get_retry
#            delay_before_retry
#            connect_port
#        }
#    }
}

check_nginx.sh

!/bin/bash
status=$(ps -C nginx --no-heading|wc -l)
if [ "${status}" = "" ]; then
        /bin/systemctl start  nginx.service #redhat7
        /etc/init.d/nginx start  #centos
        status2=$(ps -C nginx --no-heading|wc -l)
        if [ "${status2}" = ""  ]; then
             /bin/systemctl stop  keepalived.service #redhat7
             /etc/init.d/keepalived start  #centos
        fi
fi