集群（3）

LVS && HA

1.DR模式实现lvs

Server11端作为调度器

Sever11操作

首先配置yum源如图

Yum repolist##查看已拥有的yum仓库

安装ipvsadm

Yum install -y ipvsadm

ip addr add 172.25.15.100/32 dev eth0     ##添加一个虚拟网络172.25.15.100

ipvsadm -C      #清空转发表

ipvsadm -A -t 172.25.15.100:80 -s rr##-A添加一个虚拟服务-ttcp服务-s使用的调度算法

ipvsadm -a -t 172.25.15.100:80 -r 172.25.15.13:80 -g##-a在内核虚拟服务器表的一条记录里添加一条新的服务器-r真实服务器-g指定工作模式为直接路由模式

ipvsadm -a -t 172.25.15.100:80 -r 172.25.15.14:80 -g

 /etc/init.d/ipvsadm save##保存ipvsadm表

/etc/init.d/iptables stop##关闭防火墙

Server13 && server14

添加虚拟网络ip

yum install arptables_jf.x86_64 -y

arptables -A IN -d 172.25.15.100 -j DROP##-A追加规则-d目的地址-j跳到目标-s源地址

arptables -A OUT -s 172.25.15.100 -j mangle --mangle-ip-s 172.25.15.13

##这两条指令意思是将目的地址为172.25.15.100的包丢掉将源地址为172.25.15.100的请求包发给172.25.15.13

##server14同样操作

/etc/init.d/arptables_jf save##保存

安装httpd并开启

Yum install -y httpd

/etc/init.d/httpd start

并在默认发布目录上编辑index.html作为轮询时区别不同的虚拟机

Cd /var/www/html

Server13:

Echo <h1>server13.example.com</h1> >index.html

Server14:

Echo <h1>server14.example.com</h1> >index.html

测试1

真机curl虚拟ipcurl 172.25.15.100会发现server13 && server14轮询

测试2

当关闭serever13端的lvs时轮询访问的server13会中断

但下图会发现server11 ipvsadm -l 查询时并不会发现错误所以说明lvs本身没有健康检查功能

2.配置ldirectord 服务

想要有监测功能需要加入ldirectord服务

先配置ldirectord 服务:

Server11:

yum install ldirectord-3.9.5-3.1.x86_64.rpm

 cd /etc/ha.d/

cp /usr/share/doc/ldirectord-3.9.5/ldirectord.cf .

vim ldirectord.cf

测试

/etc/init.d/ldirectord start

轮询正常且虚拟服务存在

当server13关闭httpd服务时server11端再ipvsadm测试会发现server13虚拟服务已经关闭且curl 172.25.15.100时只会访问server14

所以安装ldirectord 服务会具有健康检查功能

3.将ldirectord服务加入heartbeat 服务中

先将server11 && server12中的httpldirectord服务关掉并删掉虚拟网络

/etc/init.d/ldirectord stop

/etc/init.d/httpd stop

ip addr del 172.25.15.100/24 dev eth0

两边虚拟机都修改配置文件加入ldirectord服务

vim haresources

两边虚拟机都启动heartbeat服务

/etc/init.d/heartbeat start

测试1

都启动服务后客户端正常访问且服务正常轮询虚拟网络服务正常运行

测试2

当集群中server11关掉hearbeat服务时server12会自动接管服务而且客户端会正常工作

4.keepalived + lvs

1用httpd服务测试

Server11端

下载keepalived-1.2.24.tar.gz压缩包并解压

 tar zxf keepalived-1.2.24.tar.gz

安装软件包解决依赖性

yum install -y ipvsadm kernel-devel openssl-devel popt-devel libnl-devel gcc make -y

yum install libnfnetlink-devel-1.0.0-1.el6.x86_64.rpm

./configure --prefix=/usr/local/keepalived

make && make install

做四个软连接

ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/

ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

ln -s /usr/local/keepalived/etc/keepalived/ /etc/

 ln -s /usr/local/keepalived/sbin/keepalived /usr/sbin/

Scp到server12上来

scp -r keepalived/ root@172.25.15.12:/usr/local/

Server12同样做软连接“

ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/

ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

ln -s /usr/local/keepalived/etc/keepalived/ /etc/

ln -s /usr/local/keepalived/sbin/keepalived /usr/sbin/

Server11端

 cd /etc/keepalived/

vim keepalived.conf

scp keepalived.conf root@172.25.15.12:/etc/keepalived/##发送给server12

Server 11 && server12 都安装mailx用来接受邮件

yum install -y mailx

Server12端

修改server11端传过来的keepalived的配置文件

Cd /etc/keepalived

Vim keepalived.conf

##修改备份机状态为BACKUP以及备份机优先级为50

主机与备份机两边都给执行权限并开启

chmod +x /etc/init.d/keepalived

/etc/init.d/keepalived start

测试

正常启动后用 ip addr show 查看会发现真实运行在server11上但是ipvsadm会发现在备份机上也存在说明数据同时备份。当server11挂掉后数据就可继续运行不用从0开始

而且对客户端的访问并没有影响

2用ftp服务测试

Server13 && server14端都安装vsftp服务

分别创建server13以及server14文件用来区分连接的虚拟机

Server11&& server12端

Vim keepalived.conf

Server13 && server14端

添加172.25.15.200虚拟ip:

Server11 &&server12端启动服务

/etc/init.d/keepalived start

测试

当server13断开服务时会自动切到server13上来