Lvs+Keepalived高可用负载均衡配置

o2geao

　　 Lvs+Keepalived高可用负载均衡配置
　　环境介绍：
vip=192.168.3.80   (负载均衡虚拟ip)
lvs+keepalived_master          eth0:172.20.27.81  eth1:192.168.3.81 (1核1G)
lvs+keepalived_back             eth0:172.20.27.82  eth1:192.168.3.82 (1核1G)
web01                                    eth0:172.20.27.83  eth1:192.168.3.83 (1核1G)
web02                                    eth0:172.20.27.84  eth1:192.168.3.84 (1核1G)
　　一、在(lvs主备节点)安装
1.安装依赖包：
yum install -y gcc gcc-c++ makepcre pcre-devel kernel-devel openssl-devel libnl-devel popt-devel popt-static
modprobe -l | grep ipvs //检查linux内核是否集成lvs模块：
echo "1" >/proc/sys/net/ipv4/ip_forward //开启路由转发功能：　　2.安装ipvsadm
wget http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.26.tar.gz
tar zxvf ipvsadm-1.26.tar.gz
cd ipvsadm-1.26
make && make install　　3.安装keepalived
3.1安装配置keepalived
wget http://www.keepalived.org/software/keepalived-1.2.15.tar.gz
tar zxvf keepalived-1.2.15.tar.gz
cd keepalived-1.2.15
./configure --prefix=/usr/local/keepalived
make && make install　　3.2将keepalived配置成系统服务
cp /usr/local/keepalived/etc/rc.d/init.d/keepalived  /etc/init.d/
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
mkdir /etc/keepalived/
cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
cp /usr/local/keepalived/sbin/keepalived /usr/sbin/　　3.3修改keepalived配置文件
3.3.1修改lvs+keepalived_master的keepalived配置文件
echo '' >/etc/keepalived/keepalived.conf //清空配置文件，自己写
vim /etc/keepalived/keepalived.conf! Configuration File forkeepalived
global_defs {
notification_email {
331095659@qq.com    #故障接受联系人
}
notification_email_from 331095659@qq.com    #故障发送人
smtp_server 127.0.0.1   #本机发送邮件
smtp_connect_timeout 30
router_id LVS_MASTER   #lvs+keepalived_back上修改为LVS_BACKUP
}
vrrp_instance VI_1 {
state MASTER    #lvs+keepalived_back上修改为BACKUP
interface eth1
virtual_router_id 51   #虚拟路由标识，主从相同
priority 100   #lvs+keepalived_back上修改为90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111   #主从认证密码必须一致
}
virtual_ipaddress {    #Web虚拟IP（VTP）
192.168.3.80
}
}
virtual_server 192.168.3.80 80 { #定义虚拟IP和端口
delay_loop 6    #检查真实服务器时间，单位秒
lb_algo wlc      #设置负载调度算法，wlc为加权最少链接（Weighted Least Connections）比较多
lb_kind DR      #设置LVS负载均衡DR模式
persistence_timeout 60 #同一IP的连接60秒内被分配到同一台真实服务器
protocol TCP    #使用TCP协议检查realserver状态
real_server 192.168.3.83 80 {  #第一个web服务器
weight 3          #节点权重值
TCP_CHECK {       #健康检查方式
connect_timeout 3 #连接超时
nb_get_retry 3    #重试次数
delay_before_retry 3  #重试间隔/S
}
}
real_server 192.168.3.84 80 {  #第二个web服务器
weight 3
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}　　3.3.2修改lvs+keepalived_back的keepalived配置文件
echo '' >/etc/keepalived/keepalived.conf //清空配置文件，自己写
vim /etc/keepalived/keepalived.conf! Configuration File forkeepalived
global_defs {
notification_email {
331095659@qq.com   
}
notification_email_from 331095659@qq.com   
smtp_server 127.0.0.1  
smtp_connect_timeout 30
router_id LVS_BACKUP
}
vrrp_instance VI_1 {
state BACKUP   
interface eth1
virtual_router_id 51
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress
192.168.3.80
}
}
virtual_server 192.168.3.80 80 {
delay_loop 6
lb_algo wlc
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.3.83 80 {
weight 3
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
real_server 192.168.3.84 80 {
weight 3
TCP_CHECK {
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}　　3.4 启动keepalived(lvs主备节点都启动)
service keepalived restart
echo 'service keepalived start' >>/etc/rc.local　　二、分别在两台Web(web01和web02)服务器编写脚本并启动
vim /etc/init.d/real.sh
#!/bin/bash
#description : start realserver
VIP=192.168.3.80 //keepalived虚拟ip
. /etc/init.d/functions
case "$1" in
start)
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
echo "LVS RealServer Start OK"
;;
stop)
/sbin/ifconfig lo:0 down
echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
echo "LVS RealServer Stoped OK"
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esacchmod +x /etc/init.d/real.sh
/etc/init.d/real.sh start
echo "/etc/init.d/real.sh start" >> /etc/rc.local　　三、测试及常用命令
常用命令：
ipvsadm -ln #显示集群中服务器ip信息
ip addr       #显示VTP绑定在哪个服务器上
tail -f /var/log/messger
(从日志中可知，主机出现故障后，备机立刻检测到，此时备机变为MASTER角色，并且接管了主机的虚拟IP资源，最后将虚拟IP绑定在eth1设备上)