keepalived高可用

---

目录

• keepalived实现nginx负载均衡机高可用
  • 配置web网站首页
  • 部署keepalived高可用
  • 让keepalived监控nginx负载均衡机
  • 配置keepalived加入监控脚本的配置
• zabbix监控脑裂和主备切换
  • 在zabbix服务端这边，添加监控项，和报警
  • 写监控脚本
  • 添加监控项
  • 再来添加触发器
  • 模拟主备切换
• keepalived实现haproxy负载均衡机高可用
  • 首先部署好web界面
  • 部署，haproxy负载均衡
  • 开始部署keepalived高可用
  • 编写脚本
  • 配置keepalived加入监控脚本的配置

keepalived实现nginx负载均衡机高可用

环境说明

主机名	ip地址	系统信息
master	192.168.26.10	centos8
backup	192.168.26.11	centos8
RS1	192.168.26.12	centos8
RS2	192.168.26.13	centos8

配置web网站首页

RS1

//配置yum源
[root@RS1 ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@RS1 ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
[root@RS1 ~]# dnf clean all

//关闭防火墙和selinux
[root@RS1 ~]# setenforce 0
[root@RS1 ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@RS1 ~]# systemctl disable --now firewalld

//安装httpd服务，主页内容为RS1
[root@RS1 ~]# dnf -y install httpd
[root@RS1 ~]# echo "RS1" > /var/www/html/index.html
[root@RS1 ~]# systemctl enable --now httpd
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → /usr/lib/systemd/system/httpd.service.
[root@RS1 ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                   *:80                  *:*              
LISTEN  0       128                [::]:22               [::]:*              
[root@RS1 ~]# curl 192.168.26.12
RS1

RS2

//配置yum源
[root@RS2 ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@RS2 ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
[root@RS2 ~]# dnf clean all
18 files removed

//关闭防火墙和selinux
[root@RS2 ~]# setenforce 0
[root@RS2 ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@RS2 ~]# systemctl disable --now firewalld.service  

//安装nginx服务，主页内容为RS2
[root@RS2 ~]# dnf -y install nginx
[root@RS2 ~]# echo "RS2" > /usr/share/nginx/html/index.html 
[root@RS2 ~]# systemctl enable --now nginx
[root@RS2 ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:80            0.0.0.0:*              
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                [::]:80               [::]:*              
LISTEN  0       128                [::]:22               [::]:*  
[root@RS2 ~]# curl 192.168.26.13
RS2

master端

//配置yum源
[root@master ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@master ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
[root@master ~]# dnf clean all
18 files removed

//关闭防火墙和selinux
[root@master ~]# setenforce 0
[root@master ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@master ~]# systemctl disable --now firewalld.service

//安装nginx
[root@master ~]# dnf -y install nginx

//修改nginx配置文件，开启负载均衡
[root@master ~]# vim /etc/nginx/nginx.conf
http {
    ......
    upstream web {
        server 192.168.26.12 ;
        server 192.168.26.13 ;
    }
    server {
        .......
        location / {
        proxy_pass   http://web ;
        root html ;
        }
    }
}

//重启服务测试访问
[root@master ~]# curl 192.168.26.10
RS2
[root@master ~]# curl 192.168.26.10
RS1
[root@master ~]# curl 192.168.26.10
RS2
[root@master ~]# curl 192.168.26.10
RS1

backup

//配置yum源
[root@backup ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@backup ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
[root@backup ~]# dnf clean all
//关闭防火墙和selinux
[root@backup ~]# setenforce 0
[root@backup ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@backup ~]# systemctl disable --now firewalld.service

//安装nginx
[root@backup ~]# dnf -y install nginx

//修改nginx配置文件，开启负载均衡
[root@backup ~]# vim /etc/nginx/nginx.conf
http {
    ......
    upstream web {
        server 192.168.26.12 ;
        server 192.168.26.13 ;
    }
    server {
        .......
        location / {
        proxy_pass   http://web ;
        root html ;
        }
    }
}

//重启服务测试访问
[root@backup ~]# systemctl restart nginx
[root@backup ~]# curl 192.168.26.11
RS1
[root@backup ~]# curl 192.168.26.11
RS2
[root@backup ~]# curl 192.168.26.11
RS1
[root@backup ~]# curl 192.168.26.11
RS2

部署keepalived高可用

master

//安装keepalived
[root@master ~]# yum -y install keepalived

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

global_defs {
   router_id lb01
}

vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass zhangdezhi
    }
    virtual_ipaddress {
        192.168.26.250 
    }
}

virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@master ~]# systemctl start keepalived
[root@master ~]# systemctl enable keepalived
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever

//通过虚拟ip访问
一定要把backup端的nginx服务关掉才能访问
[root@backup ~]# systemctl stop nginx
[root@backup ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                [::]:22               [::]:*       

[root@master ~]# curl 192.168.26.250
RS2
[root@master ~]# curl 192.168.26.250
RS1

backup

//安装keepalived
[root@backup ~]# yum -y install keepalived

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

global_defs {
   router_id lb02
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass zhangdezhi
    }
    virtual_ipaddress {
        192.168.26.250
    }
}

virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup ~]# systemctl start keepalived
[root@backup ~]# systemctl enable keepalived

让keepalived监控nginx负载均衡机

keepalived通过脚本来监控nginx负载均衡机的状态
在master上编写脚本

[root@master ~]# mkdir /scripts
[root@master ~]# cd /scripts/
[root@master scripts]# vim check_nginx.sh
#!/bin/bash
nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
if [ $nginx_status -lt 1 ];then
    systemctl stop keepalived
fi
[root@master scripts]# chmod +x check_nginx.sh 
[root@master scripts]# vim notify.sh
#!/bin/bash
VIP=$2
case "$1" in
  master)
        nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
        if [ $nginx_status -lt 1 ];then
            systemctl start nginx
        fi
        sendmail
  ;;
  backup)
        nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
        if [ $nginx_status -gt 0 ];then
            systemctl stop nginx
        fi
  ;;
  *)
        echo "Usage:$0 master|backup VIP"
  ;;
esac

[root@master scripts]# chmod +x notify.sh 
[root@master scripts]# ll
total 8
-rwxr-xr-x. 1 root root 142 Oct  8 11:55 check_nginx.sh
-rwxr-xr-x. 1 root root 451 Oct  8 11:56 notify.sh

在backup上编写脚本

[root@backup ~]# mkdir /scripts
[root@backup ~]# cd /scripts/
[root@backup scripts]# scp root@192.168.26.10:/scripts/notify.sh .
[root@backup scripts]# ll
total 4
-rwxr-xr-x. 1 root root 451 Oct  8 11:56 notify.sh

配置keepalived加入监控脚本的配置

master端

[root@master scripts]# vim /etc/keepalived/keepalived.conf 
[root@master scripts]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived

global_defs {
   router_id lb01
}


vrrp_script nginx_check {		//增加这一块
    script "/scripts/check_nginx.sh"
    interval 1
    weight -20
}


vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass zhangdezhi
    }
    virtual_ipaddress {
        192.168.26.250 
    }
    track_script {	    
        nginx_check                //增加这一块
    }
    notify_master "/scripts/notify.sh master 192.168.26.250"	
}


virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@master ~]# systemctl restart keepalived

backup端
backup无需检测nginx是否正常，当升级为MASTER时启动nginx，当降级为BACKUP时关闭

[root@backup scripts]# vim /etc/keepalived/keepalived.conf 
[root@backup scripts]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived

global_defs {
   router_id lb02
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass zhangdezhi
    }
    virtual_ipaddress {
        192.168.26.250
    }
    notify_master "/scripts/notify.sh master 192.168.26.250"    //增加这里
    notify_backup "/scripts/notify.sh backup 192.168.26.250"
}

virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup ~]# systemctl restart keepalived

测试

//master端，nginx服务出现异常
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever
[root@master ~]# curl 192.168.26.250
RS2
[root@master ~]# curl 192.168.26.250
RS1
[root@master ~]# systemctl stop nginx
[root@master ~]# systemctl status keepalived
● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; enabled; vend>
   Active: inactive (dead) since Sun 2022-10-09 08:40:45 EDT; 4s ago
  Process: 2129 ExecStart=/usr/sbin/keepalived $KEEPALIVED_OPTIONS (code=exi>
 Main PID: 2130 (code=exited, status=0/SUCCESS)

//backup成功转接vip
[root@backup ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:54:aa:ad brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.11/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe54:aaad/64 scope link 
       valid_lft forever preferred_lft forever
[root@backup ~]# curl 192.168.26.11
RS1
[root@backup ~]# curl 192.168.26.11
RS2

zabbix监控脑裂和主备切换

主机名	ip地址	服务	系统信息
zabbix	192.168.26.131	httpd mysql php zabbix	centos8
master	192.168.26.10	nginx keepalived	centos8
backup	192.168.26.11	nginx keepalived zabbix_agentd	centos8
RS1	192.168.26.12	httpd	centos8
RS2	192.168.26.13	nginx	centos8

部署zabbix

再部署好上面的高可用

在backup端安装zabbix_agentd监控项

//创建zabbix用户
[root@backup ~]# useradd -rMs /sbin/nologin zabbix

//安装依赖包
[root@backup ~]# dnf -y install make gcc gcc-c++ pcre-devel openssl openssl-devel wget

//下载zabbix软件包
[root@backup ~]# wget https://cdn.zabbix.com/zabbix/sources/stable/6.2/zabbix-6.2.2.tar.gz

//解压并进行安装
[root@backup ~]# tar -xf zabbix-6.2.2.tar.gz
[root@backup ~]# cd zabbix-6.2.2/
[root@backup zabbix-6.2.2]# ./configure --enable-agent
......
[root@backup zabbix-6.2.2]# make install

//修改配置文件
[root@backup ~]# cd /usr/local/etc/
[root@backup etc]# ls
zabbix_agentd.conf  zabbix_agentd.conf.d
[root@backup etc]# vim zabbix_agentd.conf
………
Server=192.168.26.131
…………
ServerActive=192.168.26.131
…………
Hostname=backup

//启动zabbix_agentd服务
[root@backup ~]# zabbix_agentd 
[root@backup ~]# ss -anlt
State   Recv-Q  Send-Q   Local Address:Port      Peer Address:Port  Process  
LISTEN  0       128            0.0.0.0:80             0.0.0.0:*              
LISTEN  0       128            0.0.0.0:22             0.0.0.0:*              
LISTEN  0       128            0.0.0.0:10050          0.0.0.0:*              
LISTEN  0       128               [::]:80                [::]:*              
LISTEN  0       128               [::]:22                [::]:*  

在zabbix服务端这边，添加监控项，和报警

添加监控主机

写监控脚本

[root@backup ~]# cd /scripts/
[root@backup scripts]# vim check_keepalived.sh
[root@backup scripts]# cat check_keepalived.sh 
#!/bin/bash
  
if [ `ip a show ens160 |grep 192.168.26.250|wc -l` -ne 0 ];then
    echo "1"
else
    echo "0"
fi
[root@backup scripts]# chmod +x check_keepalived.sh 

//修改配置文件
[root@backup scripts]# vim /usr/local/etc/zabbix_agentd.conf
UnsafeUserParameters=1
UserParameter=check_keepalived,/bin/bash /scripts/check_keepalived.sh

//重启服务
[root@backup scripts]# pkill zbbix
[root@backup scripts]# zabbix_agentd 
[root@backup scripts]# ss -anlt
State   Recv-Q  Send-Q   Local Address:Port      Peer Address:Port  Process  
LISTEN  0       128            0.0.0.0:80             0.0.0.0:*              
LISTEN  0       128            0.0.0.0:22             0.0.0.0:*              
LISTEN  0       128            0.0.0.0:10050          0.0.0.0:*              
LISTEN  0       128               [::]:80                [::]:*              
LISTEN  0       128               [::]:22                [::]:*              

添加监控项

再来添加触发器

模拟主备切换

RS1
[root@master ~]# curl 192.168.26.250
RS2
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever
[root@master ~]# systemctl stop nginx.service 
[root@master ~]#  systemctl status keepalived.service 
● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; enabled; vend>
   Active: inactive (dead) since Sun 2022-10-09 18:37:40 EDT; 3s ago
  Process: 2773 ExecStart=/usr/sbin/keepalived $KEEPALIVED_OPTIONS (code=exi>
 Main PID: 2774 (code=exited, status=0/SUCCESS)


[root@backup ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:54:aa:ad brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.11/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe54:aaad/64 scope link 
       valid_lft forever preferred_lft forever
[root@backup ~]# curl 192.168.26.250
RS1
[root@backup ~]# curl 192.168.26.250
RS2

报警触发

keepalived实现haproxy负载均衡机高可用

环境说明

主机名	ip地址	服务	系统信息
master	192.168.26.10	haproxy keepalived	centos8
backup	192.168.26.11	haproxy keepalived	centos8
RS1	192.168.26.12	httpd	centos8
RS2	192.168.26.13	nginx	centos8

首先部署好web界面

RS1

//配置yum源
[root@RS1 ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@RS1 ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo

//关闭防火墙和selinux
[root@RS1 ~]# setenforce 0
[root@RS1 ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@RS1 ~]# systemctl disable --now firewalld.service 

//安装httpd服务，主页内容为RS1
[root@RS1 ~]# dnf -y install httpd
[root@RS1 ~]# echo "RS1" > /var/www/html/index.html
[root@RS1 ~]# systemctl enable --now httpd.service 
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → /usr/lib/systemd/system/httpd.service.
[root@RS1 ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                   *:80                  *:*              
LISTEN  0       128                [::]:22               [::]:*    
[root@RS1 ~]# curl 192.168.26.12
RS1

RS2

//配置yum源
[root@RS2 ~]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@RS2 ~]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo

//关闭防火墙和selinux
[root@RS2 ~]# setenforce 0
[root@RS2 ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@RS2 ~]# systemctl disable --now firewalld.service  

//安装nginx服务，主页内容为RS2
[root@RS2 ~]# dnf -y install nginx
[root@RS2 ~]# echo "RS2" > /usr/share/nginx/html/index.html 
[root@RS2 ~]# systemctl enable --now nginx.service 
Created symlink /etc/systemd/system/multi-user.target.wants/nginx.service → /usr/lib/systemd/system/nginx.service.
[root@RS2 ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:80            0.0.0.0:*              
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                [::]:80               [::]:*              
LISTEN  0       128                [::]:22               [::]:*              
[root@RS2 ~]# curl 192.168.26.13
RS2

部署，haproxy负载均衡

master端

//关闭防火墙和selinux
[root@master ~]# setenforce 0
[root@master ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@master ~]# systemctl disable --now firewalld.service  

//创建用户
[root@master ~]# useradd -rMs /sbin/nologin haproxy

//下载依赖包
[root@master ~]# dnf -y install make gcc pcre-devel bzip2-devel openssl-devel systemd-devel wget vim

//下载haproxy压缩包
[root@master ~]# wget https://src.fedoraproject.org/repo/pkgs/haproxy/haproxy-2.6.0.tar.gz/sha512/7bb70bfb5606bbdac61d712bc510c5e8d5a5126ed8827d699b14a2f4562b3bd57f8f21344d955041cee0812c661350cca8082078afe2f277ff1399e461ddb7bb/haproxy-2.6.0.tar.gz

//解压并安装
[root@master haproxy-2.6.0]# make -j $(grep 'processor' /proc/cpuinfo |wc -l)  \
> TARGET=linux-glibc  \
> USE_OPENSSL=1  \
> USE_ZLIB=1  \
> USE_PCRE=1  \
> USE_SYSTEMD=1

[root@master haproxy-2.6.0]# make install PREFIX=/usr/local/haproxy

//复制命令到/usr/sbin目录下
[root@master haproxy-2.6.0]# cp haproxy /usr/sbin/

//修改内核参数
[root@master ~]# vim /etc/sysctl.conf
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1

[root@master ~]# sysctl -p
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1

//修改配置文件
[root@master ~]# mkdir /etc/haproxy
[root@master ~]# vim /etc/haproxy/haproxy.cfg
[root@master ~]# cat /etc/haproxy/haproxy.cfg 
global
    daemon
    maxconn 256
 
defaults
    mode http
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms
 
frontend http-in
    bind *:80
    default_backend servers
 
backend servers
    server web01 192.168.26.12:80
    server web02 192.168.26.13:80

//编写service文件，并启动服务
[root@master ~]# vim /usr/lib/systemd/system/haproxy.service  
[root@master ~]# cat /usr/lib/systemd/system/haproxy.service 
[Unit]
Description=HAProxy Load Balancer
After=syslog.target network.target
 
[Service]
ExecStartPre=/usr/local/haproxy/sbin/haproxy -f /etc/haproxy/haproxy.cfg   -c -q
ExecStart=/usr/local/haproxy/sbin/haproxy -Ws -f /etc/haproxy/haproxy.cfg  -p /var/run/haproxy.pid
ExecReload=/bin/kill -USR2 $MAINPID
 
[Install]
WantedBy=multi-user.target

[root@master ~]# systemctl daemon-reload
[root@master ~]# systemctl start haproxy.service
[root@master ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:80            0.0.0.0:*              
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                [::]:22               [::]:*   

//查看负载均衡效果           
[root@master ~]# curl 192.168.26.10
RS1
[root@master ~]# curl 192.168.26.10
RS2
[root@master ~]# curl 192.168.26.10
RS1
[root@master ~]# curl 192.168.26.10
RS2

backup端

//关闭防火墙和selinux
[root@backup ~]# setenforce 0
[root@backup ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[root@backup ~]# systemctl disable --now firewalld.service  

//创建用户
[root@backup ~]# useradd -rMs /sbin/nologin haproxy


//下载依赖包
[root@backup ~]# dnf -y install make gcc pcre-devel bzip2-devel openssl-devel systemd-devel wget vim

//下载haproxy压缩包
[root@backup ~]# wget https://src.fedoraproject.org/repo/pkgs/haproxy/haproxy-2.6.0.tar.gz/sha512/7bb70bfb5606bbdac61d712bc510c5e8d5a5126ed8827d699b14a2f4562b3bd57f8f21344d955041cee0812c661350cca8082078afe2f277ff1399e461ddb7bb/haproxy-2.6.0.tar.gz

//解压并安装
[root@backup haproxy-2.6.0]# make -j $(grep 'processor' /proc/cpuinfo |wc -l)  \
> TARGET=linux-glibc  \
> USE_OPENSSL=1  \
> USE_ZLIB=1  \
> USE_PCRE=1  \
> USE_SYSTEMD=1

[root@backup haproxy-2.6.0]# make install PREFIX=/usr/local/haproxy

//复制命令到/usr/sbin目录下
[root@backup haproxy-2.6.0]# cp haproxy /usr/sbin/

//修改内核参数
[root@backup ~]# vim /etc/sysctl.conf
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1

[root@backup haproxy-2.6.0]# sysctl -p
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1

//修改配置文件
[root@backup ~]# mkdir /etc/haproxy
[root@backup ~]# vim /etc/haproxy/haproxy.cfg
[root@backup ~]# cat /etc/haproxy/haproxy.cfg 
global
    daemon
    maxconn 256
 
defaults
    mode http
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms
 
frontend http-in
    bind *:80
    default_backend servers
 
backend servers
    server web01 192.168.26.12:80
    server web02 192.168.26.13:80

//编写service文件，并启动服务
[root@backup ~]# vim /usr/lib/systemd/system/haproxy.service
[root@backup ~]# cat /usr/lib/systemd/system/haproxy.service 
[Unit]
Description=HAProxy Load Balancer
After=syslog.target network.target
 
[Service]
ExecStartPre=/usr/local/haproxy/sbin/haproxy -f /etc/haproxy/haproxy.cfg   -c -q
ExecStart=/usr/local/haproxy/sbin/haproxy -Ws -f /etc/haproxy/haproxy.cfg  -p /var/run/haproxy.pid
ExecReload=/bin/kill -USR2 $MAINPID
 
[Install]
WantedBy=multi-user.target

[root@backup ~]# systemctl daemon-reload 
[root@backup ~]# systemctl start haproxy.service 
[root@backup ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128             0.0.0.0:80            0.0.0.0:*              
LISTEN  0       128                [::]:22               [::]:*     

//查看负载均衡效果         
[root@backup ~]# curl 192.168.26.11
RS1
[root@backup ~]# curl 192.168.26.11
RS2
[root@backup ~]# curl 192.168.26.11
RS1
[root@backup ~]# curl 192.168.26.11
RS2
//backup端的负载均衡器最好关掉
[root@backup ~]# systemctl stop haproxy.service 

开始部署keepalived高可用

master 端配置

//首先安装keepalived
[root@master ~]# dnf -y install keepalived

//编辑配置文件，并启动服务
[root@master ~]# vim /etc/keepalived/keepalived.conf
[root@master ~]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
 
global_defs {
   router_id lb01
}
 
vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        192.168.26.250
    }
}
 
virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP
 
    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
 
    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

[root@master ~]# systemctl enable --now keepalived.service 
Created symlink /etc/systemd/system/multi-user.target.wants/keepalived.service → /usr/lib/systemd/system/keepalived.service.

//通过虚拟ip访问
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever

[root@master ~]# curl 192.168.26.250
RS1
[root@master ~]# curl 192.168.26.250
RS2
[root@master ~]# curl 192.168.26.250
RS1
[root@master ~]# curl 192.168.26.250
RS2

backup端

//首先安装keepalived
[root@backup ~]# dnf -y install keepalived

//编辑配置文件，并启动服务
[root@backup ~]# vim /etc/keepalived/keepalived.conf
[root@backup ~]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
 
global_defs {
   router_id lb02
}
 
vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        192.168.26.250
    }
}
 
virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP
 
    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
 
    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup ~]# systemctl enable --now keepalived.service 
Created symlink /etc/systemd/system/multi-user.target.wants/keepalived.service → /usr/lib/systemd/system/keepalived.service.

编写脚本

master端

[root@master ~]# mkdir /scripts
[root@master ~]# cd /scripts/
[root@master scripts]# vim check_haproxy.sh
[root@master scripts]# cat check_haproxy.sh 
#!/bin/bash
haproxy_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bhaproxy\b'|wc -l)
if [ $haproxy_status -lt 1 ];then
    systemctl stop keepalived
fi

[root@master scripts]# vim notify.sh
[root@master scripts]# cat notify.sh 
#!/bin/bash
VIP=$2
case "$1" in
  master)
        haproxy_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bhaproxy\b'|wc -l)
        if [ $haproxy_status -lt 1 ];then
            systemctl start haproxy
        fi
  ;;
  backup)
        haproxy_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bhaproxy\b'|wc -l)
        if [ $haproxy_status -gt 0 ];then
            systemctl stop haproxy

[root@master scripts]# chmod +x check_haproxy.sh notify.sh 
[root@master scripts]# ll
total 8
-rwxr-xr-x. 1 root root 148 Oct  9 20:48 check_haproxy.sh
-rwxr-xr-x. 1 root root 377 Oct  9 20:48 notify.sh

backup端

[root@backup ~]# mkdir /scripts
[root@backup ~]# cd /scripts/
[root@backup scripts]# scp root@192.168.26.10:/scripts/notify.sh .
The authenticity of host '192.168.26.10 (192.168.26.10)' can't be established.
ECDSA key fingerprint is SHA256:byoKSQZ3ZjLOFT0RGTkPB20XCMYYI7KBlKRDQSfIY5s.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.26.10' (ECDSA) to the list of known hosts.
root@192.168.26.10's password: 
notify.sh                                  100%  377   393.6KB/s   00:00    
[root@backup scripts]# ll
total 4
-rwxr-xr-x. 1 root root 377 Oct 10 16:50 notify.sh

配置keepalived加入监控脚本的配置

master端

[root@master ~]# vim /etc/keepalived/keepalived.conf 
[root@master ~]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
 
global_defs {
   router_id lb01
}
 
vrrp_script haproxy_check {		
    script "/scripts/check_haproxy.sh"
    interval 1
    weight -20
}

vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        192.168.26.250
    }
    track_script {	
        haproxy_check
    }
    notify_master "/scripts/notify.sh master 192.168.26.250"	
}
 
virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP
 
    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
 
    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

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

backup端
backup无需检测nginx是否正常，当升级为MASTER时启动nginx，当降级为BACKUP时关闭

[root@backup scripts]# vim /etc/keepalived/keepalived.conf 
[root@backup scripts]# cat /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
 
global_defs {
   router_id lb02
}
 
vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        192.168.26.250
    }
    notify_master "/scripts/notify.sh master 192.168.26.250"
    notify_backup "/scripts/notify.sh backup 192.168.26.250"
}
 
virtual_server 192.168.26.250 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP
 
    real_server 192.168.26.10 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
 
    real_server 192.168.26.11 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

[root@backup scripts]# systemctl restart keepalived.service 

测试，模拟haproxy服务故障

//master端
[root@master ~]# curl 192.168.26.250
RS1
[root@master ~]# curl 192.168.26.250
RS2
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever
[root@master ~]# systemctl stop haproxy
[root@master ~]# ss -anlt
State   Recv-Q  Send-Q    Local Address:Port     Peer Address:Port  Process  
LISTEN  0       128             0.0.0.0:22            0.0.0.0:*              
LISTEN  0       128                [::]:22               [::]:*              
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:2b:1b:38 brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.10/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe2b:1b38/64 scope link 
       valid_lft forever preferred_lft forever


//backup端
[root@backup ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:54:aa:ad brd ff:ff:ff:ff:ff:ff
    inet 192.168.26.11/24 brd 192.168.26.255 scope global noprefixroute ens160
       valid_lft forever preferred_lft forever
    inet 192.168.26.250/32 scope global ens160
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe54:aaad/64 scope link 
       valid_lft forever preferred_lft forever
[root@backup ~]# curl 192.168.26.250
RS1
[root@backup ~]# curl 192.168.26.250
RS2