centos7安裝部署keepalived

安裝環境說明

• 兩臺服務器，系統centos7
• 服務器1 IP 192.168.2.191
• 服務器2 IP 192.168.2.192
• 軟件版本，keepalived-1.3.5.tar.gz
• keepalive安裝包百度雲連接 密碼：hmd7
• 服務器1 VIP 192.168.2.95
• 服務器2 VIP 192.168.2.96
• 本次配置，服務器1和服務器2互爲主備

編譯安裝

# tar zxvf keepalived-1.3.5.tar.gz     #解壓
# cd keepalived-1.3.5/
# ./configure
# make && make install      #編譯安裝

配置文件

• 機器1配置

在/etc/keepalived/ 目錄下建立keepalived.conf

# vim /etc/keepalived/keepalived.conf     #添加如下內容

! 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          #網卡接口名稱
    virtual_router_id 51
    priority 101 
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }   
    virtual_ipaddress {
        192.168.2.95       #虛擬地址1
    }   
    track_script {
       chk_nginx
    }
}
vrrp_instance VI_2 {
    state BACKUP
    interface eth0           #網卡接口名
    virtual_router_id 52
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.2.96    #虛擬地址2
    }
    track_script {
       chk_nginx
    }
}

• 服務器2配置

在/etc/keepalived/ 目錄下建立keepalived.conf

vim /etc/keepalived/keepalived.conf     #添加如下內容

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            #網卡名稱
    virtual_router_id 51
    priority 100 
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }   
    virtual_ipaddress {
        192.168.2.95      #虛擬地址1
    }   
    track_script {
       chk_nginx
    }
}
vrrp_instance VI_2 {
    state MASTER
    interface eth0         #網卡名稱
    virtual_router_id 52
    priority 101
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.2.96      #虛擬地址2
    }
    track_script {
       chk_nginx
    }
}

• nginx檢查腳本

# 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

系統服務配置

# 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

啓動命令

# systemctl enable keepalived.service  # 設置開機自啓動
# systemctl start keepalived.service
# systemctl stop keepalived.service

注意事項

防火牆啓用狀態下執行

# 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

修改爲單播通訊

服務器網絡環境中，路由交換層禁用了ARP的廣播限制，形成了keepalived主備協議沒法經過廣播的方式進行通訊，形成主備兩臺服務器都強制佔用HAVIP地址，出現同時兩臺服務器都有VIP地址的狀況出現。必須經過配置來指定IP的兩臺服務器間進行通

須要修改配置文件

priority 100
    unicast_src_ip  192.168.2.192    #本機實際IP
    unicast_peer {
             192.168.2.191         #對端實際IP
    }

另外一臺服務器配置類似，只是互換IP地址

驗證

服務啓動後，可查看VIP是否綁定

# ip addr

顯示結果