nginx+keepalived负载均衡及高可用

一、环境准备

|-------------|-----------------------------------------|-----------------|
| 主机名 | ip地址 | 备注 |
| openEuler-1 | 192.168.121.11（本机） 192.168.131.11（心跳连接） | nginx主负载均衡调度器 |
| openEuler-2 | 192.168.121.12（本机） 192.168.131.12（心跳连接） | nginx-2主负载均衡调度器 |
| openEuler-3 | 192.168.121.13 | web1 |
| openEuler-4 | 192.168.121.14 | web2 |
| Rocky-1 | 192.168.121.51 | client |

二、配置nginx反向代理

[root@openEuler-1 ~]# cd /etc/nginx/conf.d/
[root@openEuler-1 conf.d]# vim lb.conf
upstream webs {
        server 192.168.121.13:80;
        server 192.168.121.14:80;
}

server {
        location / {
                proxy_pass http://webs;
        }
}
[root@openEuler-1 conf.d]# scp lb.conf 192.168.121.12:$PWD

# 重启nginx服务

三、配置keepalived

[root@openEuler-1 conf.d]# cd /etc/keepalived/
[root@openEuler-1 keepalived]# vim keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id LVS_1
}

vrrp_script check_nginx {
        script "killall -0 nginx"
}

vrrp_instance VI_1 {
    state MASTER
    interface ens160
    lvs_sync_daemon_interface ens192
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }

    track_script {
        check_nginx
    }

    virtual_ipaddress {
        192.168.121.10
    }
}

# 副负载均衡调度器上稍作修改
[root@openEuler-1 keepalived]# scp keepalived.conf 192.168.121.12:$PWD
修改为；
! Configuration File for keepalived

global_defs {
   router_id LVS_2
}

vrrp_script check_nginx {
        script "killall -0 nginx"
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    lvs_sync_daemon_interface ens192
    virtual_router_id 51
    priority 80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }

    track_script {
        check_nginx
    }

    virtual_ipaddress {
        192.168.121.10
    }
}

# 两台调度器都重启keepalived服务

四、测试

# 关闭nginx主负载调度器
[root@openEuler-1 ~]# systemctl stop nginx.service

# 副负载调度器接管服务
[root@openEuler-2 ~]# tail -f /var/log/messages
Mar  2 16:25:16 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:16 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:16 openEuler-2 kernel: [ 9964.205163] IPVS: stopping backup sync thread 3081 ...
Mar  2 16:25:16 openEuler-2 kernel: [ 9964.208213] IPVS: sync thread started: state = MASTER, mcast_ifn = ens192, syncid = 0, id = 0
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: (VI_1) Sending/queueing gratuitous ARPs on ens160 for 192.168.121.10
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10
Mar  2 16:25:21 openEuler-2 Keepalived_vrrp[3078]: Sending gratuitous ARP on ens160 for 192.168.121.10