linux keepalived安装

Last updated on July 18, 2025 am

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centos8.5安装配置keepalived

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rpm安装keepalived

需要安装包邮箱联系我

sudo rpm -ivh net-snmp-libs-5.7.2-49.el7.x86_64.rpm
rpm -ql net-snmp-agent-libs | grep libnetsnmpmibs.so
sudo rpm -ivh net-snmp-agent-libs-5.7.2-49.el7.x86_64.rpm
rpm -ql net-snmp-agent-libs | grep libnetsnmpagent.so
sudo rpm -ivh keepalived-1.3.5-19.el7.x86_64.rpm
keepalived --version

keepalived命令

sudo systemctl stop keepalived
sudo systemctl reload keepalived
sudo systemctl restart keepalived
sudo systemctl enable keepalived
sudo systemctl start keepalived
sudo systemctl status keepalived

配置文件

sudo vim /etc/keepalived/keepalived.conf

注意事项1 - 关闭严格检查

! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   # vrrp_skip_check_adv_addr       # 最好关闭，默认为false
   # vrrp_strict                    # 最好关闭严格检查
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state MASTER                    # 当前实例MASTER/BACKUP
    interface eth0                  # 绑定的网卡
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.200.16 label eth0:0 # 虚拟ip1 
        192.168.200.17 label eth0:1 # 最好添加标签  label eth0:0
        192.168.200.18 label eth0:2
    }
}

主配置

Keepalived自v2.0以后支持多个节点同时为 MASTER，否则只能有一个MASTER

vrrp_instance VI_1 {
    state MASTER                     # MASTER BACKUP
    interface eth0                   # 替换为实际网卡名
    virtual_router_id 51             # VRID 标识，主备必须一致
    priority 100                     # 优先级MASTER比BACKUP高，MASTER:100
    advert_int 1                     # VRRP 报文发送间隔
    authentication {
        auth_type PASS
        auth_pass 1111               # 认证密码，主备一致
    }
    virtual_ipaddress {
      192.168.25.176 label eth0:0    # 虚拟 IP 地址
    }
}

从配置

vrrp_instance VI_1 {
    state BACKUP
    interface eth0                    # 替换为实际网卡名
    virtual_router_id 51              # 必须与 MASTER 一致
    priority 99                       # 低于 MASTER 的优先级,BACKUP:99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111                # 认证密码，主备一致
    }
    virtual_ipaddress {
        192.168.25.176                # 虚拟 IP 地址
    }
}

监测连通性

ping 192.168.25.176
sudo tcpdump -i eth0 host 192.168.25.176 and icmp

查看keepalived日志

sudo tail -f /var/log/messages
sudo journalctl -u keepalived -f

脚本健康检查

sudo vim /etc/keepalived/check_app.sh

#!/bin/bash

# 检查 nginx 是否在监听 80 端口
nc -z 127.0.0.1 80
if [ $? -eq 0 ]; then
    exit 0
else
    exit 1
fi

sudo chmod a+x /etc/keepalived/check_app.sh
sudo vim /etc/keepalived/keepalived.conf

vrrp_script check_app {
    script "/etc/keepalived/check_app.sh"
    interval 2                                    # 每2秒执行一次
    timeout 2                                     # 脚本超时时间
    rise 2                                        # 成功2次才认为服务正常
    fall 3                                        # 失败3次才认为服务异常
}

vrrp_instance VI_1 {
    
    ...

    track_script {
        check_app
    }
}

sudo systemctl reload keepalived
sudo systemctl restart keepalived
sudo systemctl status keepalived

网卡分析虚拟ip

注意：
关闭防火墙
systemctl stop firewalld
关闭iptables
firewall-cmd –add-icmp-block-inversion
firewall-cmd –add-rich-rule=’rule protocol value=”icmp” accept’

# 查看网卡是否绑定虚拟ip
sudo ip addr show eth0
# inet 192.168.25.176/32 scope global eth0
# 主节点才会有

# 检查网卡是否开启混合模型
ip link show eth0
# th0: <BROADCAST,MULTICAST,UP,LOWER_UP,PROMISC> ...
# 开启混合模式
# sudo ip link set eth0 promisc on

# 查看网卡
ip addr
ip addr show

# 查看路由表
ip route show

# 手动添加ip到路由表【临时】
#sudo ip route add 192.168.25.176 dev eth0 scope link
#sudo ip addr add 192.168.25.176 dev lo

# 永久添加ip到路由表
vim /etc/sysconfig/network-scripts/route-eth0
# 192.168.25.176 dev eth0 scope link
systemctl restart network # 重启网卡

# 查看虚拟ip映射
sudo ipvsadm -Ln

nginx统一负载

sudo vim /usr/local/nginx/conf/nginx.conf

http {
  
  upstream dehoop_nginx_servers {
    ip_hash;
    server 192.168.21.187:80 weight=1 max_fails=3 fail_timeout=30s;
    server 192.168.21.188:80 weight=1 max_fails=3 fail_timeout=30s;
  }

  upstream dehoop_admin_servers {
    ip_hash;
    server 192.168.21.187:30104 weight=1 max_fails=3 fail_timeout=30s;
    server 192.168.21.188:30104 weight=1 max_fails=3 fail_timeout=30s;
  }
  
  server {
    ...
    location /dehoop/ {      
      proxy_pass http://dehoop_nginx_servers/;
    }

    location /dehoop-api/ {      
      proxy_set_header Host $host;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_pass http://dehoop_admin_servers/;
    }
    
    location /dehoop-admin/app{
      root   /usr/local/nginx/html/;
      index index.html;
      try_files $uri $uri/ /dehoop-admin/app/index.html;
    }
  }
}

初始化模版

! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.200.16
        192.168.200.17
        192.168.200.18
    }
}

virtual_server 192.168.200.100 443 {
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.201.100 443 {
        weight 1
        SSL_GET {
            url {
              path /
              digest ff20ad2481f97b1754ef3e12ecd3a9cc
            }
            url {
              path /mrtg/
              digest 9b3a0c85a887a256d6939da88aabd8cd
            }
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

virtual_server 10.10.10.2 1358 {
    delay_loop 6
    lb_algo rr 
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    sorry_server 192.168.200.200 1358

    real_server 192.168.200.2 1358 {
        weight 1
        HTTP_GET {
            url { 
              path /testurl/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl2/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl3/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.200.3 1358 {
        weight 1
        HTTP_GET {
            url { 
              path /testurl/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334c
            }
            url { 
              path /testurl2/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334c
            }
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

virtual_server 10.10.10.3 1358 {
    delay_loop 3
    lb_algo rr 
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.200.4 1358 {
        weight 1
        HTTP_GET {
            url { 
              path /testurl/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl2/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl3/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.200.5 1358 {
        weight 1
        HTTP_GET {
            url { 
              path /testurl/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl2/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            url { 
              path /testurl3/test.jsp
              digest 640205b7b0fc66c1ea91c463fac6334d
            }
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}