CentOS 6.3下部署LVS(NAT)+keepalived实现高性能高可用负载均衡

我就是我 2022-04-23 00:00 38阅读 0赞

**一、简介**

VS/NAT原理图：

![2012082012002614.gif][]

二、**系统环境**

实验拓扑：

![2012081717141291.jpg][]

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  
net.ipv4.ip\_forward = 1  
\[root@CentOS-LVS\_MASTER ~\]\# sysctl -p

3、配置Keepalived

\[root@CentOS-LVS\_MASTER ~\]\# less /etc/keepalived/keepalived.conf

![复制代码][copycode.gif]

! 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 } } }

![复制代码][copycode.gif]

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  
\[root@WEB1 ~\]\# cd /var/www/html/  
\[root@WEB1 html\]\# cat index.html  
<h1>WEB1/192.168.10.4</h1>  
\[root@WEB1 html\]\# /etc/init.d/httpd start  
另一台机器配置一样，过程略。

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

![2012082410252367.jpg][]

![2012082410270018.jpg][]

**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

![lvs][]

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。

![2012082410365890.jpg][]

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

![2012082410394133.jpg][]

![2012082410401438.jpg][]

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)

![2012082410420635.jpg][]

重新启动WEB2节点的服务，日志信息如下：

![2012082410423552.jpg][]

![2012082410430629.jpg][]

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）

![2012082410433584.jpg][]

[2012082012002614.gif]: /images/20220325/34c9970c8d68469993a3740fd3b03401.png
[2012081717141291.jpg]: /images/20220325/f4a87dfc47904d2fbcc842df4115831e.png
[copycode.gif]: /images/20220325/44bfca45e8dd40b1ad247f3e65c1ab7e.png
[2012082410252367.jpg]: /images/20220325/0ab9325155374afab1b69f18d6307010.png
[2012082410270018.jpg]: /images/20220325/fad3163d0c1146238899095097258a77.png
[lvs]: /images/20220325/b0adca63577a4eedaafc542f1b0cf594.png
[2012082410365890.jpg]: /images/20220325/ab1b11678bfa43c89c62029fb6a54e79.png
[2012082410394133.jpg]: /images/20220325/888020bd846a45f382420496d4e7faa4.png
[2012082410401438.jpg]: /images/20220325/6e533e564cd34450bfbc593e8fd4c8ce.png
[2012082410420635.jpg]: /images/20220325/decda1028760448787036c875c435491.png
[2012082410423552.jpg]: /images/20220325/7602a034c241416bb87167009f2c8c93.png
[2012082410430629.jpg]: /images/20220325/1d3feb7e4f1548008e2a2093382cb84e.png
[2012082410433584.jpg]: /images/20220325/38ff69ea3b564106bfa74fc9fbf806b1.png