之前已经配置好了mysql-cluster群集，由于日常sql节点通常都大于1台，这意味着应用程序一部分要使用sql1节点，一部分使用sql2节点，当然，所有的应用程序只需要一个节点，但这样不在群集节点间做分流负载，也就不必做群集了，另外，如果一个群集节点down机了，随之而来的程序也down掉，该如何解决，因此我用keepalived来实现对sql节点的高可用，问题又来了，这里的keepalived存在单机故障，所以准备2台互备，我们用lvs来实现负载均衡，这样其中一个节点或者keepalived坏掉，应用程序将仍然可以工作，因为负载均衡器将请求转到了工作正常的另外一个节点，我们需要一个虚拟IP地址:192.168.18.100。它会安排给这个MySQL群集的负载均衡,以便于应用程序通过统一单独的IP地址来访问群集。 

回想一下之前的部署ip结构:

 

192.168.18.10：MGM/SQL1

192.168.18.11：NDBD1/lvs+keepalived

192.168.18.12：NDBD2/lvs+keepalived

192.168.18.9  :   SQL2

VIP：192.168.18.100
 
1.在11/12这2台设备上安装lvs+keepalived
[root@localhost  home]yum -y install ipvsadm
[root@localhost  home]tar -zxf keepalived-1.2.7.tar.gz
[root@localhost  home]cd keepalived-1.2.7
[root@localhost keepalived-1.2.7]#  ./configure --prefix=/usr/local/keepalived/
[root@localhost keepalived-1.2.7]#make && make install
[root@localhost keepalived-1.2.7]#vi /usr/local/keepalived/keepalived.conf
 
! Configuration File for keepalived
 
global_defs {
 router_id LVS_DEVEL
}
 
vrrp_instance VI_1 {
 state MASTER       ＃备机上改为BACKUP
 interface eth1
 virtual_router_id 51
 priority 100
 advert_int 3
 authentication {
 auth_type PASS
 auth_pass 1111
 }
 virtual_ipaddress {
 192.168.18.100
 }
}
 
virtual_server 192.168.18.100 3306 {
 delay_loop 6
 lb_algo rr
 lb_kind DR
 persistence_timeout 60
 protocol TCP
 
real_server 192.168.18.9 3306 {
 weight 1
 TCP_CHECK {
 connect_timeout 3
 nb_get_retry 3
 delay_before_retry 3
 connect_port 3306
 }
}
real_server 192.168.18.10 3306 {
 weight 1
 TCP_CHECK{
 connect_timeout 3
 nb_get_retry 3
 delay_before_retry 3
 connect_port 3306
 }
}
}
 
启动keepalived：
[root@localhost  home]/usr/local/keepalived/sbin/keepalived -D -f /usr/local/keepalived/keepalived.conf
 
2.在2台sql节点行编辑如下脚本
[root@localhost  home]vi re.sh
 
#!/bin/sh
VIP=192.168.18.100
/etc/rc.d/init.d/functions
case "$1" in
start)
echo "Start LVS of RealServer"
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
route add -host $VIP dev lo:0
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
;;
stop)
/sbin/ifconfig lo:0 down
echo "Stop LVS of RealServer"
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 "Usage:$0{start|stop}"
exit 1
esac
 
[root@localhost  home] chmod +x re.sh
[root@localhost  home]./re.sh start

 好了，现在可以直接利用vip，192.168.18.100来连接了