一、简介 VS/NAT原理图:
二、系统环境 实验拓扑:
系统平台:CentOS 6.3 Kernel:2.6.32-279.el6.i686 LVS版本:ipvsadm-1.26 keepalived版本:keepalived-1.2.4 三、安装 0、安装LVS前系统需要安装popt-static,kernel-devel,make,gcc,openssl-devel,lftp,libnl*,popt* 1、在两台Director Server上分别配置LVS+Keepalived LVS install ------------- [root@CentOS-LVS_MASTER ~]# wget http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.26.tar.gz [root@CentOS-LVS_MASTER ~]# ln -s /usr/src/kernels/2.6.32-279.el6.i686//usr/src/linux/ [root@CentOS-LVS_MASTER ~]# tar zxvf ipvsadm-1.26.tar.gz [root@CentOS-LVS_MASTER ~]# cd ipvsadm-1.26 [root@CentOS-LVS_MASTER ipvsadm-1.26]# make && make install Keepalived install ------------- [root@CentOS-LVS_MASTER ~]# wget http://www.keepalived.org/software/keepalived-1.2.4.tar.gz [root@CentOS-LVS_MASTER ~]# tar zxvf keepalived-1.2.4.tar.gz [root@CentOS-LVS_MASTER ~]# cd keepalived-1.2.4 [root@CentOS-LVS_MASTER keepalived-1.2.4]# ./configure && make && make install ######### 将keepalived做成启动服务,方便管理########## [root@CentOS-LVS_MASTER ~]# cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/ [root@CentOS-LVS_MASTER ~]# cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/ [root@CentOS-LVS_MASTER ~]# mkdir /etc/keepalived/ [root@CentOS-LVS_MASTER ~]# cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/ [root@CentOS-LVS_MASTER ~]# cp /usr/local/sbin/keepalived /usr/sbin/ [root@CentOS-LVS_MASTER ~]# service keepalived start | stop 2、开启路由转发
[root@CentOS-LVS_MASTER ~]# vim /etc/sysctl.conf 3、配置Keepalived [root@CentOS-LVS_MASTER ~]# less /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { router_id LVS_MASTER #BACKUP上修改为LVS_BACKUP } vrrp_instance VI_1 { state MASTER #BACKUP上修改为BACKUP interface eth0 virtual_router_id 51 priority 100 #BACKUP上修改为80 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 10.0.0.227 } } vrrp_instance LAN_GATEWAY { state MASTER #BACKUP上修改为LVS_BACKUP interface eth1 virtual_router_id 52 priority 100 #BACKUP上修改为80 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.10.10 } } virtual_server 10.0.0.227 80 { delay_loop 6 lb_algo rr lb_kind NAT # persistence_timeout 5 protocol TCP real_server 192.168.10.4 80 { weight 3 TCP_CHECK { connect_timeout 3 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } real_server 192.168.10.5 80 { weight 3 TCP_CHECK { connect_timeout 3 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } } BACKUP服务器同上配置,先安装lvs再安装keepalived,然后配置/etc/keepalived/keepalived.conf,只需将批注部分改一下即可。 4、分别在2台Real Server上面设置网关 把网关都设置成:192.168.10.10 5、在2台RealServer中分别配置HTTP
[root@WEB1 ~]# yum -y install httpd 6、分别在CentOS-LVS_MASTER、CentOS-LVS_BACKUP上执行service keepalived start启动keepalived就可实现负载均衡及高可用集群了; [root@CentOS-LVS_MASTER keepalived]# service keepalived start
四、测试 ####高可用性测试#### 模拟故障,将CentOS-LVS_MASTER上的keepalived服务停掉,然后观察CentOS-LVS_BACKUP上的日志,信息如下
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etho设备上。 将CentOS-LVS_MASTER 上的keepalived服务开启后,CentOS-LVS_BACKUP的日志状态。
从日志可知,备机在检测到主机重新恢复正常后,释放了虚拟IP资源重新成为BACKUP角色 ####故障切换测试#### 故障切换是测试当某个节点出现故障后,Keepalived监制模块是否能及时发现然后屏蔽故障节点,同时将服务器转移到正常节点来执行。 将WEB2节点服务停掉,假设这个节点出现故障,然后主、备机日志信息如下
从以上可以看出,Keepalived监控模块检测到192.168.10.5这台主机出现故障后,将WEB2从集群系统中剔除掉了。 此时访问http://10.0.0.227只能看到WEB1了)
重新启动WEB2节点的服务,日志信息如下:
Keepalived监控模块检测到192.168.10.5这台主机恢复正常后,又将此节点加入集群系统中,再次访问就可以访问到WEB2页面了) (责任编辑:IT) |