keepalived是用来干什么的:
keepalived是用来检测web服务器的状态,当有一台服务器死机,或者出现故障时。keepalived可以将这台服务器从系统集群中剔除,当检测到web服务器恢复正常时,会自动加入服务器集群。这些操作都是自动完成,不需要人工干涉。人工需要做的就是修复出现问题的服务器。
一.安装keepalived
1.在http://www.keepalived.org/官网下载文件
2.将文件复制到系统目录下面
3.解压文件:tar -zxvf 文件路径
4.安装依赖包:yum install popt-devel -y
5.执行编译前操作:执行./configure --prefix=/usr/local/keepalived
6.执行编译并且安装: 执行make && make install
二.将keepalived加入系统服务,开机自动启动
mkdir /etc/keepalived
cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf
cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
cp /usr/local/keepalived/sbin/keepalived /usr/sbin/
chkconfig --level 2345 keepalived on //注册开机启动
三.keepalived配置
打开keepalived配置,配置主机内容:
global_defs {
#notification_email {
# root@localhost
# }
#notification_email_from root@localhost
# smtp_server localhost
# smtp_connect_timeout 30
router_id NodeA //负载均衡器标识,同一网段内,可以相同
}
vrrp_instance VI_1 {
state MASTER #指定A节点为主节点 备用节点上设置为BACKUP即可
interface eth0 #绑定虚拟IP的网络接口
virtual_router_id 51 #VRRP组名,两个节点的设置必须一样,以指明各个节点属于同一VRRP组
priority 100 #主节点的优先级(1-254之间),备用节点必须比主节点优先级低
advert_int 1 #组播信息发送间隔,两个节点设置必须一样
authentication { #设置验证信息,两个节点必须一致
auth_type PASS
auth_pass 1111
}
virtual_ipaddress { #指定虚拟IP, 两个节点设置必须一样
10.0.2.220
}
}
virtual_server 10.0.2.220 80 {
delay_loop 6 //健康检查时间,单位是秒
lb_algo rr //负载调度算法,这里设置为rr,即轮询算法
lb_kind NAT //LVS实现负载均衡的机制,可以有NAT、TUN和DR三个模式可选
nat_mask 255.255.255.0
persistence_timeout 50 //会话保持时间,单位是秒(可以适当延长时间以保持session)
protocol TCP //转发协议类型,有tcp和udp两种
real_server 10.0.2.32 80 {
weight 1 //权重
TCP_CHECK { //通过tcpcheck判断RealServer的健康状态
connect_timeout 5 //连接超时时间
nb_get_retry 3 //重连次数
delay_before_retry 3 //重连间隔时间
connect_port 80 //检测端口
}
}
}
备机的配置和主机一样,不同的是
state MASTER改为state BACKUP