web集群(haproxy负载均衡+keepalived高可用)

主机名	主机	IP地址
lvs1	haproxy+keepalived	192.168.88.38
proxy	haproxy+keepalived	192.168.88.66
web1	nginx	192.168.88.10
web2	nginx	192.168.88.20

配置lvs1，proxy

安装haproxy

[root@lvs1 ~]# yum -y install haproxy
[root@lvs1 ~]# vim /etc/haproxy/haproxy.cfg 
[root@lvs1 ~]# cat /etc/haproxy/haproxy.cfg 
global
    #log         127.0.0.1 local2
    log /dev/log local0 info
    log /dev/log local0 notice
    #chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon
    nbproc 1
    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats

defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000
listen stats
    bind    *:9000
    mode    http
    stats   enable
    stats   hide-version
    stats   uri       /stats
    stats   refresh   30s
    stats   realm     Haproxy\ Statistics
    stats   auth      admin:admin
listen web 0.0.0.0:80 
      balance roundrobin  balance roundrobin    #负载均衡调度算法
     server web1 192.168.88.10:80 check inter 2000 fall 3
check inter 2000  fall 3     #表示启用对此后端服务器执行健康检查，设置健康状态检查的时间间隔，单位为毫秒连续三次检测不到心跳频率则认为该节点失效
     server web2 192.168.88.20:80 check inter 2000 fall 3
[root@lvs1 ~]# systemctl start haproxy.service 
proxy主机步骤如上

安装keepalived

#主节点
[root@lvs1 ~]# yum -y install keepalived
[root@lvs1 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   # 通知邮件服务器的配置
   notification_email {
     # 当master失去VIP或则VIP的时候，会发一封通知邮件到your-email@qq.com
     your-email@qq.com
   }
   # 发件人信息
   notification_email_from keepalived@qq.com
   # 邮件服务器地址
   smtp_server 127.0.0.1
   # 邮件服务器超时时间
   smtp_connect_timeout 30
   # 邮件TITLE
   router_id lvs1
}
vrrp_script check_nginx {  
   #检查haproxy宕机，关闭keepalived服务
   script "/etc/keepalived/check_haproxy.sh"
   interval 3
}
vrrp_instance VI_1 {
    # 主机: MASTER
    # 备机: BACKUP
    state MASTER
    # 实例绑定的网卡, 用ip a命令查看网卡编号
    interface ens37
    # 虚拟路由标识，这个标识是一个数字(1-255)，在一个VRRP实例中主备服务器ID必须一样
    virtual_router_id 88
    # 优先级，数字越大优先级越高，在一个实例中主服务器优先级要高于备服务器
    priority 90
    # 主备之间同步检查的时间间隔单位秒
    advert_int 1
    # 验证类型和密码
    authentication {
        # 验证类型有两种 PASS和HA
        auth_type PASS
        # 验证密码，在一个实例中主备密码保持一样
        auth_pass 11111111
    }
    # 虚拟IP地址,可以有多个，每行一个
    virtual_ipaddress {
        192.168.88.88/24
    }
     track_script {
    check_nginx 
   }
}
[root@lvs1 ~]# systemctl start keepalived
#从节点
[root@proxy ~]# yum -y install keepalived
[root@proxy ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   # 通知邮件服务器的配置
   notification_email {
     # 当master失去VIP或则VIP的时候，会发一封通知邮件到your-email@qq.com
     your-email@qq.com
   }
   # 发件人信息
   notification_email_from keepalived@qq.com
   # 邮件服务器地址
   smtp_server 127.0.0.1
   # 邮件服务器超时时间
   smtp_connect_timeout 30
   # 邮件TITLE
   router_id proxy
}
vrrp_script check_nginx {
   script "/etc/keepalived/check_nginx.sh"
   interval 3
}
vrrp_instance VI_1 {
    # 主机: MASTER
    # 备机: BACKUP
    state BACKUP
    # 实例绑定的网卡, 用ip a命令查看网卡编号
    interface ens37
    # 虚拟路由标识，这个标识是一个数字(1-255)，在一个VRRP实例中主备服务器ID必须一样
    virtual_router_id 88
    # 优先级，数字越大优先级越高，在一个实例中主服务器优先级要高于备服务器
    priority 80
    # 主备之间同步检查的时间间隔单位秒
    advert_int 1
    # 验证类型和密码
    authentication {
        # 验证类型有两种 PASS和HA
        auth_type PASS
        # 验证密码，在一个实例中主备密码保持一样
        auth_pass 11111111
    }
    # 虚拟IP地址,可以有多个，每行一个
    virtual_ipaddress {
        192.168.88.88/24
    }
    track_script {
    check_nginx 
   }
}
[root@proxy ~]# systemctl start keepalived

验证

此时使用ip a查看，vip地址在主节点上
[root@lvs1 ~]# ip a
3: ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:48:b3:7b brd ff:ff:ff:ff:ff:ff
    inet 192.168.88.38/24 brd 192.168.88.255 scope global noprefixroute ens37
       valid_lft forever preferred_lft forever
    inet 192.168.88.88/24 scope global secondary ens37
       valid_lft forever preferred_lft forever
    inet6 fe80::dbb5:b534:a44a:a21/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
[root@lvs1 ~]# curl 192.168.88.88
test2
[root@lvs1 ~]# curl 192.168.88.88
test1
[root@lvs1 ~]# curl 192.168.88.88
test1
[root@lvs1 ~]# curl 192.168.88.88
test2
假如把主节点的haproxy服务关闭，查看keepalived是否会自动关闭，并且把vip地址漂浮到从节点
[root@lvs1 ~]# systemctl status keepalived.service 
● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; disabled; vendor preset: disabled)
   Active: active (running) since 日 2024-03-17 23:35:28 CST; 24min ago
[root@lvs1 ~]# systemctl stop haproxy.service 
[root@lvs1 ~]# systemctl status keepalived.service 
● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; disabled; vendor preset: disabled)
[root@lvs1 ~]# ip a
3: ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:48:b3:7b brd ff:ff:ff:ff:ff:ff
    inet 192.168.88.38/24 brd 192.168.88.255 scope global noprefixroute ens37
       valid_lft forever preferred_lft forever
    inet6 fe80::dbb5:b534:a44a:a21/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
[root@proxy ~]# ip a
3: ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:e4:cd:ac brd ff:ff:ff:ff:ff:ff
    inet 192.168.88.66/24 brd 192.168.88.255 scope global noprefixroute ens37
       valid_lft forever preferred_lft forever
    inet 192.168.88.88/24 scope global secondary ens37
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fee4:cdac/64 scope link 
       valid_lft forever preferred_lft forever       
发现配置的检查haproxy脚本生效，vip地址也漂浮到了proxy从节点上
[root@ceph01 ~]# curl 192.168.88.88
test2
[root@ceph01 ~]# curl 192.168.88.88
test1
[root@ceph01 ~]# curl 192.168.88.88
test1
[root@ceph01 ~]# curl 192.168.88.88
test2

总结

通过以上验证，实现了使用haproxy来达到负载均衡的效果，keepalived来达到HA的效果。保证的web集群正常访问