介绍

Linux：keepalived 双热备份（基础备份web）

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环境

 一台 centos7    keepalived    ipvsadm    （主服务器） 192.168.254.1

 一台 centos7    keepalived    ipvsadm    （备份服务器）  192.168.254.2

漂移ip  ：  192.168.254.66

 一台 centos7    web   （web1）  192.168.254.3

 一台 centos7    web   （web2）    192.168.254.3

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 在主服务器上的配置

yum -y install keepalived ipvsadm

systemctl enable keepalived.service 

mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak

vim /etc/keepalived/keepalived.conf

写入

bal_defs {
   router_id tarro1
}


vrrp_instance VI_1 {
    state MASTER
    interface ens33
    virtual_router_id 1
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123123
    }
    virtual_ipaddress {
        192.168.254.66

    }
}

virtual_server 192.168.254.66 80 {
        delay_loop 15
        lb_algo rr
        lb_kind DR
        protocol TCP

                real_server 192.168.254.3 80 {
        weight 1
        TCP_CHECK {
                connect_port 80
                connect_timeout 3
                nb_get_retry 3
                delay_before_retry 4
                }
        }


                real_server 192.168.254.4 80 {
        weight 1
        TCP_CHECK {
                connect_port 80
                connect_timeout 3
                nb_get_retry 3
                delay_before_retry 4
                }
        }
}

 

systemctl restart keepalived

modprobe ip_vs

echo "modprobe ip_vs" >>/etc/rc.local

---

备份服务器上的配置

yum -y install ipvsadm keepalived

systemctl enable keepalived.service 

mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak

vim /etc/keepalived/keepalived.conf

写入

bal_defs {
   router_id tarro2
}


vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 1
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123123
    }
    virtual_ipaddress {
        192.168.254.66

    }
}

virtual_server 192.168.254.66 80 {
        delay_loop 15
        lb_algo rr
        lb_kind DR 
        protocol TCP
    
                real_server 192.168.254.3 80 {
        weight 1
        TCP_CHECK {
                connect_port 80
                connect_timeout 3
                nb_get_retry 3
                delay_before_retry 4
                }
        }


                real_server 192.168.254.4 80 {
        weight 1
        TCP_CHECK {
                connect_port 80
                connect_timeout 3
                nb_get_retry 3
                delay_before_retry 4
                }
        }
}

modprobe ip_vs

echo "modprobe ip_vs" >>/etc/rc.local

systemctl restart keepalived

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web1服务器配置

yum -y install httpd

systemctl enable httpd

systemctl start httpd

echo "<h1>192.168.254.3" > /var/www/html/index.html

 

 

vim /etc/sysconfig/network-scripts/ifcfg-lo:0

写入

DEVICE=lo:0
IPADDR=192.168.254.66
NETMASK=255.255.255.255
ONBOOT=yes

systemctl restart network

 

echo "route add -host 192.168.254.66 dev lo:0" >>/etc/rc.local

route add -host 192.168.254.66 dev lo:0

vim /etc/sysctl.conf

末尾插入

net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2

sysctl -p

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web2服务器配置

yum -y install httpd

systemctl enable httpd

systemctl start httpd

echo "<h1>192.168.254.4" > /var/www/html/index.html

vim /etc/sysconfig/network-scripts/ifcfg-lo:0

写入

DEVICE=lo:0
IPADDR=192.168.254.66
NETMASK=255.255.255.255
ONBOOT=yes

systemctl restart network

echo "route add -host 192.168.254.66 dev lo:0" >>/etc/rc.local

route add -host 192.168.254.66 dev lo:0

vim /etc/sysctl.conf

末尾插入

net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2

sysctl -p

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测试效果

 

现在主服务器上有漂移地址和虚拟主机列表

 备份主机上也有虚拟列表 但是没有66的漂移地址就对了，因为现在我们的主服务器还在正常工作

现在访问192.168.254.66 就可以被lvs服务器把流量分到两个web服务器上 

我们把254.4关闭一下

 

一下就到3了  ！！！ 这里我只是在先效果，实际的环境lvs并不是备份，而是负载均衡，我们的lvs主服务器会把流量分到两个web站点上，然而两个web站点在实际中界面内容是一样的，这里只是为了看效果

现在可以看到上面lvs效果已经成功了

现在去测试keepalived效果

我们把主服务器关机

在主服务器关机的瞬间，我们的备份服务器立马会有漂移地址，我们再去访问254.66 

 

依然不影响访问 

我们再开启主服务器

漂移地址立马就回到主服务器了，测试成功