centos7安装部署keepalived

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安装环境说明

• 两台服务器，系统centos7
  
• 服务器1 IP 192.168.2.191
  
• 服务器2 IP 192.168.2.192
  
• 软件版本，keepalived-1.3.5.tar.gz
  
• keepalive安装包百度云链接 密码：hmd7
  
• 服务器1 VIP 192.168.2.95
  
• 服务器2 VIP 192.168.2.96
  
• 本次配置，服务器1和服务器2互为主备
  

编译安装

# tar zxvf keepalived-1.3.5.tar.gz     #解压
# cd keepalived-1.3.5/
# ./configure
# make && make install      #编译安装

配置文件

• 机器1配置
  

　　在/etc/keepalived/ 目录下创建keepalived.conf

# vim /etc/keepalived/keepalived.conf     #添加以下内容
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}   
notification_email_from www@example.com
smtp_server mail.example.com
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_nginx {
script "/etc/keepalived/check_nginx.sh"
interval 2
weight -5  
fall 3   
rise 2
}
vrrp_instance VI_1 {
state MASTER
interface eth0          #网卡接口名称
virtual_router_id 51
priority 101
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}   
virtual_ipaddress {
192.168.2.95       #虚拟地址1
}   
track_script {
chk_nginx
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0           #网卡接口名
virtual_router_id 52
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.2.96    #虚拟地址2
}
track_script {
chk_nginx
}
}

• 服务器2配置
  

　　在/etc/keepalived/ 目录下创建keepalived.conf

vim /etc/keepalived/keepalived.conf     #添加以下内容
Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from www@example.com
smtp_server mail.example.com
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_nginx {
script "/etc/keepalived/check_nginx.sh"
interval 2
weight -5
fall 3
rise 2
}
vrrp_instance VI_1 {
state BACKUP
interface eth0            #网卡名称
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}   
virtual_ipaddress {
192.168.2.95      #虚拟地址1
}   
track_script {
chk_nginx
}
}
vrrp_instance VI_2 {
state MASTER
interface eth0         #网卡名称
virtual_router_id 52
priority 101
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.2.96      #虚拟地址2
}
track_script {
chk_nginx
}
}

• nginx检查脚本
  

# vim /etc/keepalived/check_nginx.sh
#!/bin/bash
counter=$(ps -C nginx --no-heading|wc -l)
if [ "${counter}" = "0" ]; then
/usr/local/nginx/sbin/nginx
sleep 2
counter=$(ps -C nginx --no-heading|wc -l)
if [ "${counter}" = "0" ]; then
service keepalived stop
fi
fi
# chmod +x check_nginx.sh
系统服务配置

# vim /lib/systemd/system/keepalived.service
[Unit]
Description=LVS and VRRP High Availability Monitor
After=syslog.target network.target
[Service]
Type=simple
PIDFile=/usr/local/var/run/keepalived.pid
KillMode=process
EnvironmentFile=-/usr/local/etc/sysconfig/keepalived
ExecStart=/usr/local/sbin/keepalived --dont-fork -D
ExecReload=/bin/kill -HUP $MAINPID
[Install]
WantedBy=multi-user.target

启动命令

# systemctl enable keepalived.service  # 设置开机自启动
# systemctl start keepalived.service
# systemctl stop keepalived.service
注意事项
　　防火墙启用状态下执行

# firewall-cmd --direct --permanent --add-rule ipv4 filter INPUT 0 \
--in-interface enp0s8 --destination 224.0.0.18 --protocol vrrp -j ACCEPT
# firewall-cmd --direct --permanent --add-rule ipv4 filter OUTPUT 0 \
--out-interface enp0s8 --destination 224.0.0.18 --protocol vrrp -j ACCEPT
# firewall-cmd --reload

修改成单播通信
　　服务器网络环境中，路由交换层禁用了ARP的广播限制，造成了keepalived主备协议无法通过广播的方式进行通信，造成主备两台服务器都强制占用HAVIP地址，出现同时两台服务器都有VIP地址的情况出现。必须通过配置来指定IP的两台服务器间进行通
　　需要修改配置文件

    priority 100
unicast_src_ip  192.168.2.192    #本机实际IP
unicast_peer {
192.168.2.191         #对端实际IP
}
　　另一台服务器配置相似，只是互换IP地址

验证
　　服务启动后，可查看VIP是否绑定

# ip addr
　　显示结果