Keepalived
（lvs-DR模式下如果server1调度器挂了怎么办）
1，创建4个子虚拟机
2，server1安装keepalived
tar zxf keepalived-2.0.6.tar.gz
查看INSTALL文件
安装三部曲都在keepalived-2.0.6目录下进行
./configure --prefix=/usr/local/keepalived --with-init=SYSV #改变安装路径，此过程不能报错，可以有警告，需要根据INSTALL文件解决一些依赖性
make
make install
3，配置
chmod +x /usr/local/keepalived/etc/rc.d/init.d/keepalived
ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
ln -s /usr/local/keepalived/etc/keepalived /etc/
ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
ln -s /usr/local/keepalived/sbin/keepalived /sbin/
4，启动测试可以正常打开keepalived，然后关闭
5，将/usr/local/keealived/传到server4/usr/local下，这里需要在server1和server4安装scp命令,同样建立4个软连接
6，修改server1的keepalived的配置文件
/etc/keepalived/keepalived.conf
global_defs {
notification_email {
root@localhost #给本机发邮件
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
vrrp_skip_check_adv_addr
#vrrp_strict # 这个必须要注释，否则会在iptables加一条DROP
vrrp_garp_interval 0
vrrp_gna_interval 0
}
vrrp_instance VI_1 {
state MASTER #MASTER
interface eth0
virtual_router_id 28
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
172.25.28.100 #vip
}
}
virtual_server 172.25.28.100 80 { #vip
delay_loop 3 # 等待3s
lb_algo rr
lb_kind DR ##这里一定要改为DR
#persistence_timeout 50 #注释
protocol TCP
real_server 172.25.28.2 80 { #rip
weight 1
TCP_CHECK{
connect_timeout 3
retry 3
delay_before_retry 3
}
}
real_server 172.25.28.3 80 { #rip，如果还有服务器可以继续添加
weight 1 #server2和server3的权重相等，如果这个改为2，那么server2出现的次数就比server3多，这用在server2的服务器性能更优秀
TCP_CHECK{
connect_timeout 3
retry 3
delay_before_retry 3
}
}
}
下面全部删除不要留空行
7，删除server1上面的vip，启动keepalived
8，server1和server4安装mailx
9，scp此配置文件到对应目录，覆盖，在server4里面修改配置文件
vrrp_instance VI_1 {
state BACKUP #MASTER修改为BACKUP
interface eth0
virtual_router_id 28 #这个id和server1上面的必须一样
priority 50 #优先权修改为50
10，server4启动keepalived
11，在/var/log/message下查看日志
12，本机客户端curl查看论调，如果server2httpd服务stop那么等待3s之后在curl自动不显示server2的refused，server1 ipvsadm -ln查看也不会出现server2，一定要注意3s的延时
测试，如果server1挂了
本机测试发现，curl没有任何影响，并且通过mail查看server4变成了master,给自己设置了vip，开始广播，arp -an | grep 100发现mac地址就是server4上面的，如果server1复活，那么它会把master抢回来，给自己设置vip，server4变成backuo state，移去vip，arp -an | grep 100发现来自server1