[!Tip]
部署 HAProxy + keepalived

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部署 HAPorxy + keepalived

1.开启 ip 转发

打开配置文件

vim /etc/sysctl.conf

打开以下参数

net.ipv4.ip_forward = 1

使配置生效

sysctl -p

2.部署 HAProxy 以及 keepalived

2.1 安装

[!NOTE]
两台服务器都要安装

apt install keepalived haproxy -y

开启开机启动

systemctl enable haproxy && systemctl enable keepalived

开启服务

systemctl start haproxy && systemctl start keepalived

2.2 添加用户组以及用户

[!NOTE]
两台服务器都要添加

groupadd -r keepalived_script
useradd -r -s /sbin/nologin -g keepalived_script -M keepalived_script

2.3 配置 keepalived

刚安装完 keepalived 是没有配置文件的，查看 status 会提示没有配置文件

systemctl status keepalived

显示如下

● keepalived.service - Keepalive Daemon (LVS and VRRP)
   Loaded: loaded (/lib/systemd/system/keepalived.service; enabled; vendor preset: enabled)
   Active: inactive (dead)
Condition: start condition failed at Mon 2023-02-13 02:32:22 EST; 8min ago
           └─ ConditionFileNotEmpty=/etc/keepalived/keepalived.conf was not met

Feb 13 02:14:10 ha01 systemd[1]: Condition check resulted in Keepalive Daemon (LVS and VRRP) being skipped.
Feb 13 02:32:22 ha01 systemd[1]: Condition check resulted in Keepalive Daemon (LVS and VRRP) being skipped.

2.3.1 添加检测 haproxy 进程的脚本文件

[!NOTE]
两台服务器都要添加

cat > /etc/keepalived/chk_haproxy.sh <<'EOF'
#!/bin/bash
count=$(ps -ef |grep haproxy |egrep -cv "grep|$$")
if [ "$count" -eq 0 ];
then
    exit 1
else
    exit 0
fi
EOF
chmod +x /etc/keepalived/chk_haproxy.sh

2.3.2 添加 keepalived.conf 配置

2.3.2.1 添加 MASTER 主配置

cat > /etc/keepalived/keepalived.conf <<EOF
global_defs {
    script_user root
    enable_script_security
    router_id ha01                  # 虚拟路由名称
}

# HAProxy健康检查配置
vrrp_script chk_haproxy {
    script "/etc/keepalived/chk_haproxy.sh"         # 执行检测脚本
    interval 2                          # 脚本运行周期，秒
}

# 虚拟路由配置
vrrp_instance VI_1 {
    state MASTER                        # 本机实例状态，MASTER/BACKUP，备机配置文件中请写BACKUP
    interface ens192                     # 本机网卡名称，使用ifconfig命令查看
    virtual_router_id 51                # 虚拟路由编号，主备机保持一致
    priority 101                        # 本机初始权重，备机请填写小于主机的值（例如99）
    advert_int 1                        # 争抢虚地址的周期，秒
    authentication {
        auth_type PASS
        auth_pass adminPWD      # 认证类型和密码主备一样，要不然无法互相认证
    }
    virtual_ipaddress {
        192.168.1.130                  # 虚地址IP，主备机保持一致
    }
    track_script {
        chk_haproxy                     # 对应的健康检查配置
    }
}
EOF

重启服务并查看是否有 vip

systemctl restart keepalived && ip a | grep 130

显示如下即为 vip 已经设置成功

inet 192.168.1.130/32 scope global ens192

2.3.2.2 添加 BACKUP 从配置

cat > /etc/keepalived/keepalived.conf <<EOF
global_defs {
    script_user root
    enable_script_security
    router_id ha02                  # 虚拟路由名称
}

# HAProxy健康检查配置
vrrp_script chk_haproxy {
    script "/etc/keepalived/chk_haproxy.sh"         # 执行检测脚本
    interval 2                          # 脚本运行周期，秒
}

# 虚拟路由配置
vrrp_instance VI_1 {
    state BACKUP                        # 本机实例状态，MASTER/BACKUP，备机配置文件中请写BACKUP
    interface ens192                     # 本机网卡名称，使用ifconfig命令查看
    virtual_router_id 51                # 虚拟路由编号，主备机保持一致
    priority 100                        # 本机初始权重，备机请填写小于主机的值（例如99）
    advert_int 1                        # 争抢虚地址的周期，秒
    authentication {
        auth_type PASS
        auth_pass adminPWD      # 认证类型和密码主备一样，要不然无法互相认证
    }
    virtual_ipaddress {
        192.168.1.130                  # 虚地址IP，主备机保持一致
    }
    track_script {
        chk_haproxy                     # 对应的健康检查配置
    }
}
EOF

重启服务并查看状态

systemctl restart keepalived && systemctl status keepalived

2.4 配置 haproxy

添加 haproxy.cnf配置， 打开配置文件

vim /etc/haproxy/haproxy.cfg

追加以下配置

[!NOTE]
MyCat 的 ip 地址以及端口根据自己的服务器配置修改

listen admin_status
  bind :48800 ##VIP
  stats uri /admin-status ##统计页面
  stats auth admin:admin  # 设置统计页面认证的用户和密码，如果要设置多个，另起一行写入即可
  mode http
  option httplog
listen allmycat_service
  bind :33066  ##转发到 mycat 的 8066 端口，即 mycat 的服务端口
  mode tcp
  option tcplog
  option tcpka ## 是否允许向server和client发送keepalive
  option httpchk OPTIONS * HTTP/1.1\r\nHost:\ www
  balance roundrobin
  server mycat01 192.168.1.141:8066 check port 48700 inter 5s rise 2 fall 3
  server mycat02 192.168.1.142:8066 check port 48700 inter 5s rise 2 fall 3
  #srvtimeout 20000
  timeout server 20000

重启

systemctl restart haproxy

查看状态

systemctl status haproxy

查看管理界面，打开地址：192.168.1.130:48800/admin-status 输入账号密码，都是：admin。截图如下：

3.测试

3.1 测试高可用

测试 vip 是否有漂移参考：(https://janrs.com/?p=60#toc-23)

3.2 测试连接数据库

使用 vip 地址连接数据库，能够连接得上即可

mysql -u john -p -h 192.168.1.130 -P 33066