Nginx+keepalived实现七层的负载均衡的高可用(最新解决方案)

Nginx+keepalived实现七层的负载均衡的高可用

一、准备服务器

1、主机清单 主机名ip系统Proxy-master10.12.153.105centos7.5Proxy-slave10.12.153.176centos7.5Real-server110.12.153.114Centos7.5Real-server210.12.153.187centos7.5 2、配置安装nginx 所有的机器，关闭防火墙和selinux [root@proxy-master ~]# systemctl stop firewalld //关闭防火墙 [root@proxy-master ~]# sed -i s/^SELINUX=.*/SELINUX=disabled/ /etc/sysconfig/selinux //关闭selinux，重启生效 [root@proxy-master ~]# setenforce 0 　　　　　　　　//关闭selinux，临时生效

3.安装nginx， 全部4台

[root@proxy-master ~]# cd /etc/yum.repos.d/ [root@proxy-master yum.repos.d]# vim nginx.repo [nginx-stable] name=nginx stable repo baseurl=http://nginx.org/packages/centos/$releasever/$basearch/ gpgcheck=0 enabled=1 [root@proxy-master yum.repos.d]# yum install yum-utils -y [root@proxy-master yum.repos.d]# yum install nginx -y

二、部署负载均衡

1、选择两台nginx服务器作为代理服务器。

2、给两台代理服务器安装keepalived制作高可用生成VIP

3、配置nginx的负载均衡

#两台代理配置一样

1、修改nginx的配置文件，添加以下内容，

#注意：将/etc/nginx/conf.d/default.conf改名，不然转发不过去

[root@proxy-slave conf.d]# mv default.conf default.conf.back upstream backend { server 10.12.153.114:80 weight=1 max_fails=3 fail_timeout=20s; server 10.12.153.187:80 weight=1 max_fails=3 fail_timeout=20s; } server { listen 80; server_name localhost; location / { proxy_pass http://backend; proxy_set_header Host $host:$proxy_port; proxy_set_header X-Forwarded-For $remote_addr; } } 2、重启nginx [root@proxy-master ~]# nginx -s reload 3.修改server1、server2的web页面测试 [root@server2 ~]# cat >>/usr/share/nginx/html/index.html<<EOF > 187 > EOF [root@server1 html]# cat >/usr/share/nginx/html/index.html<<EOF > 114 > EOF 4..访问负载均衡

负载均衡正常 

三、Keepalived实现调度器HA

注：主/备调度器均能够实现正常调度

1、 主/备调度器安装软件 [root@proxy-master ~]# yum install -y keepalived [root@proxy-slave ~]# yum install -y keepalived 2、备份keepalived配置文件 [root@proxy-master ~]# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak 3、修改配置文件

①修改master

[root@proxy-master ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { router_id directory1 #辅助改为directory2 } ： vrrp_instance VI_1 { state MASTER #定义主还是备 interface ens33 #VIP绑定接口 virtual_router_id 80 #整个集群的调度器一致 priority 100 #back改为50 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 10.12.153.151/24 # vip } }

②修改slave

[root@proxy-slave ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { router_id directory2 } vrrp_instance VI_1 { state BACKUP #设置为backup interface ens33 nopreempt #设置到back上面，不抢占资源 virtual_router_id 80 priority 50 #辅助改为50 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 10.12.153.151/24 } } 4、启动keepalived（主备均启动） [root@proxy-master ~]# systemctl enable keepalived [root@proxy-slave ~]# systemctl start keepalived 5、通过停止keepalived来测试VIP是否飘逸

①在master，slave上查看

②停掉master的keepalived来模仿master宕机，看VIP是否飘逸

由此可见nginx的高可用成功

到此：

可以解决心跳故障keepalived

不能解决Nginx服务故障

四、解决nginx服务故障

 扩展对调度器Nginx健康检查（可选）两台都设置

1、作用

让Keepalived以一定时间间隔执行一个外部脚本，脚本的功能是当Nginx失败，则关闭本机的Keepalived

2、检查nginx健康的脚本 ! Configuration File for keepalived global_defs { router_id directory1 #辅助改为directory2 } ： vrrp_script check_nginx { script “/etc/keepalived/check_nginx_status.sh” interval 5 } vrrp_instance VI_1 { state MASTER #定义主还是备 interface ens33 #VIP绑定接口 virtual_router_id 80 #整个集群的调度器一致 priority 100 #back改为50 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 10.12.153.151/24 # vip } track_script { check_nginx } }

注：必须先启动nginx，再启动keepalived

3、测试

停止master的nginx，VIP会飘逸到salve上，

再次启动master的nginx，重启master的keepalived，VIP会飘到master上。