Keepalived+LVS-DR模式配置高可用负载均衡集群

环境: 虚拟机:VMware Workstation
操作系统:CentOS 5.5

一、keepalived+lvs-DR模式配置高可用负载均衡

拓扑如下：



二、服务器ip配置信息

1. ip_lb 主机(master) :



2.ip_lb_2 主机 (backup)



3.web1 主机



4.web2 主机



三、在master和backup分别查看是否有ipvsadm软件

1. 检查ipvsadm是否安装成功.可以直接输入

[root@localhost ~]# ipvsadm

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn

2. 检查模版是否加入内核

[root@localhost ~]# lsmod |grep ip_vs
ip_vs 78081 0

四、分别在web1和web2上面安装apache服务.

# 安装apache服务不说明了. 开放的端口是:8099

五、在master主机(192.168.96.2)和backup主机(192.168.96.22)上安装keepalived

1. keepalived-1.2.1.tar.gz # 解压这个文件并且安装 (tar -zxvf keepalived-1.2.1.tar.gz)

2. ./configure --prefix=/home/keepalived/ --with-kernel-dir=/usr/src/kernels/2.6.18-164.el5-i686

3.make

4.make install

5.配置文件的路径

cp /home/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/

cp /home/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

cp /home/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/

cp /home/keepalived/sbin/keepalived /sbin/

6.配置keepalived.conf文件.( ip_lb 主机<master> )

vim /etc/keepalived/keepalived.conf

#global define
global_defs {
router_id LVS_T1
}

vrrp_sync_group bl_group {
group {
bl_one
}
}

vrrp_instance bl_one {
state MASTER
interface eth0
lvs_sync_daemon_interface eth0
virtual_router_id 38
priority 150
advert_int 3
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.96.100
}
}

virtual_server 192.168.96.100 8099 {
delay_loop 3
lb_algo rr
lb_kind DR
persistence_timeout 1
protocol TCP

real_server 192.168.96.33 8099 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 8099
}

}

real_server 192.168.96.4 8099 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 8099
}
}
}

7、配置keepalived.conf文件.(ip_lb_2 主机 <backup> )

vim /etc/keepalived/keepalived.conf

#global define
global_defs {
router_id LVS_T2
}

vrrp_sync_group bl_group {
group {
bl_one
}
}

vrrp_instance bl_one {
state BACKUP
interface eth0
lvs_sync_daemon_interface eth0
virtual_router_id 38
priority 120
advert_int 3
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.96.100
}
}

virtual_server 192.168.96.100 8099 {
delay_loop 3
lb_algo rr
lb_kind DR
persistence_timeout 1
protocol TCP

real_server 192.168.96.33 8099 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 8099
}

}

real_server 192.168.96.4 8099 {
weight 1
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 8099
}
}
}

8. 分别在主备上启动keepalived

[root@ip_lb home]# /etc/init.d/keepalived start

Starting keepalived: [ OK ]

[root@ip_lb home]# tail -f /var/log/message



# PS:这里说的LVS.并不是用ipvsadm软件配置.而是直接用keepalived的virtual_server配置项控制的.

# 安装ipvsadm只是可以看到负载状况.其实只需要keepalived也可以实现负载均衡集群.

六、在web1和web2主机上配置LVS-DR的相关配置.

1. vim /etc/init.d/lvsDR_node （web1主机）

#! /bin/sh
# descript : start real server DR
VIP=192.168.96.100
. /etc/rc.d/init.d/functions
case "$1" in
start)
echo "start LVS of RealServer DR"
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
echo "1" > /proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" > /proc/sys/net/ipv4/conf/all/arp_announce
;;
stop)
/sbin/ifconfig lo:0 down
echo "close LVS of RealServer DR"
echo "0" > /proc/sys/net/ipv4/conf/all/arp_ignore
echo "0" > /proc/sys/net/ipv4/conf/all/arp_announce
;;
*)
echo "Usage : $0 {start|stop}"
exit 1
esac

2. 把这个文件复制到web2主机上.

3. 在web1和web2上分别启动这个脚本:

/etc/init.d/lvsDR_node start

七、web1和web2主机上开启httpd服务.

/etc/init.d/httpd start

# ================= TEST =======================================

八、测试是否可以负载均衡.

编写测试脚本:

#! /bin/sh
for((i=1;i<=100;i++));do
curl http://192.168.96.100:8099 >> /tmp/q;
done

结果:



九、测试断开一个web服务或加入一个web服务

现在关闭 web2主机(192.168.96.4) 的web 服务..

查看日志可以看到:



现在再把 web2主机(192.168.96.4)的web 服务加入进来:

查看日志可以看到:



十、 测试HA

现在模拟主(master)的keepalived主机死掉.

备机的日志文件:



可以看到备机的keepalived已经开始工作....

整个部署就完成了.

官方参考中文文档:http://www.keepalived.org/pdf/sery-lvs-cluster.pdf