Coder Nan

高可用集群

2022-5-24 Nginx

# 高可用集群

nginx宕机，请求无法生效

高可用

  1. 需要两台nginx服务器

  2. 需要keepalived

  3. 需要虚拟ip

  4. 在两台服务器安装nginx、keepalived

    #安装keepalived
$ yum install keepalived -y
$ rpm -q -a keepalived    #查看是否已经安装上
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    etc/keepalived/keepalived.conf

  5. 配置

    修改keepalived.conf

    global_defs {
	notification_email {
	  acassen@firewall.loc
	  failover@firewall.loc
	  sysadmin@firewall.loc
	}
	notification_email_from Alexandre.Cassen@firewall.loc
	smtp_ server 192.168.17.129
	smtp_connect_timeout 30
	router_id LVS_DEVEL	# LVS_DEVEL这字段在/etc/hosts文件中看；通过它访问到主机
}

vrrp_script chk_http_ port {
	script "/usr/local/src/nginx_check.sh"
	interval 2   # (检测脚本执行的间隔)2s
	weight 2  #权重，如果这个脚本检测为真，服务器权重+2
}

vrrp_instance VI_1 {
	state BACKUP   # 备份服务器上将MASTER 改为BACKUP
	interface ens33 # 网卡名称
	virtual_router_id 51 # 主、备机的virtual_router_id必须相同
	priority 100   #主、备机取不同的优先级，主机值较大，备份机值较小
	advert_int 1	#每隔1s发送一次心跳
	authentication {	# 校验方式， 类型是密码，密码1111
        auth type PASS
        auth pass 1111
    }
	virtual_ipaddress { # 虛拟ip
		192.168.17.50 # VRRP H虛拟ip地址
	}
}
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    在路径/usr/local/src/ 下编写检测脚本 nginx_check.sh

    #! /bin/bash
A=`ps -C nginx -no-header | wc - 1`
if [ $A -eq 0];then
	/usr/local/nginx/sbin/nginx
	sleep 2
	if [`ps -C nginx --no-header| wc -1` -eq 0 ];then
		killall keepalived
	fi
fi
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  6. 把两台服务器上nginx和keepalived启动

    $ systemctl start keepalived.service		#keepalived启动
$ ps -ef I grep keepalived		#查看keepalived是否启动
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  7. 测试

    停止主服务器的nginx、keepalived，从服务器启动，请求仍能正常访问

SSL配置