Linux集群实现--Keepalived-1.2.7

说明：

一、目        的：本文实现的Linux集群是基于Keepalived-1.2.7软件实现，

二、难        点：实现虚拟IP（VIP）自动切换的同时，还要同时实现虚拟MAC地址（VMAC）的切换，即无论集群中的Host如何切换，对外访问的IP和MAC始终不变

三、适用环境：当对外路由或交换机绑定主机MAC时适用

四、说        明：若无须对外绑定MAC地址，则大可简化如下配置

 

1. 环境及软件：

  1) 系统：Debian6 x32

  2) 内核：linux 3.2.0-0.bpo.3-686-pae

  3) 软件：keepalived-1.2.7

 

2. 配置：

   MASTER设备IP： eth0: 10.10.1.200/24  eth1:192.168.61.253/21

BACKUP设备IP： eth0: 10.10.1.100/24  eth1:192.168.61.252/21

   VIP： 192.168.61.248/21

 

3. 安装步骤：

  1）升级当前Debian系统内核linux 2.6.32

     a) 修改Debian源文件，添加一个向后兼容的源

deb http://ftp.cn.debian.org/debian-backports squeeze-backports main

        # nano /etc/apt/sources.list

     b) 更新Debian源文件关联并升级系统内核至3.2.0

        # aptitude update

        # aptitude -t squeeze-backports install linux-image-3.2.0-0.bpo.3-686-pae

        如果编译NVDIA的官方驱动的话，还要装：

        # aptitude -t squeeze-backports install linux-headers-3.2.0.bpo.3-686-pae

  2) 安装keepalived-1.2.7

     a) 首先要安装keepalived所依赖的组件

        # aptitude install make gcc libpopt-dev libnl-dev libcurl4-openssl-dev

     b) 将keepalived-1.2.7.tar.gz文件拷贝到/usr/local/soft下，解压，编译并安装到

/usr/local/keepalived

        # mkdir /usr/local/soft

        通过ftp将文件拷贝至/usr/local/soft

        # cd /usr/local/soft

        # tar zxvf keepalived-1.2.7.tar.gz

        # cd keepalived-1.2.7

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

        # make && make install

     c) 重置keepalived相关文件，以便开机自动启动

        # cp /usr/local/keepalived/sbin/keepalived /usr/sbin

        # mkdir /etc/sysconfig

        # cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig

        # cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/

        # nano /etc/init.d/keepalived

            修改/etc/init.d/keepalived文件，部分片段如下（蓝色--注释，红色--修改）：

                    ……

#. /etc/rc.d/init.d/functions

. /lib/lsb/init-functions

# Source configuration file (we set KEEPALIVED_OPTIONS there)

. /etc/sysconfig/keepalived

RETVAL=0

prog="keepalived"

start() {

    echo -n $"Starting $prog: "

    # keepalived ${KEEPALIVED_OPTIONS}

    keepalived -D

    RETVAL=$?

    echo  "1" >/proc/sys/net/ipv4/conf/all/arp_ignore

   echo  "1" >/proc/sys/net/ipv4/conf/all/arp_announce

   echo  "0" >/proc/sys/net/ipv4/conf/all/arp_filter

   echo  "1" >/proc/sys/net/ipv4/conf/eth1/arp_filter

    echo

    [ $RETVAL -eq 0 ] && touch/var/lock/$prog

}

stop() {

    echo -n $"Stopping $prog: "

    killproc keepalived

    RETVAL=$?

    echo  "0" >/proc/sys/net/ipv4/conf/all/arp_ignore

   echo  "0" >/proc/sys/net/ipv4/conf/all/arp_announce

   echo  "0" >/proc/sys/net/ipv4/conf/all/arp_filter

   echo  "0" >/proc/sys/net/ipv4/conf/eth1/arp_filter

    echo

    [ $RETVAL -eq 0 ] && rm -f/var/lock/$prog

}

……

    condrestart)

        if [ -f /var/lock/$prog ]; then

            stop

            start

        fi

        ;;

……

     d) 在/etc/keepalived下创建keepalived配置文件keepalived.conf

              # mkdir /etc/keepalived

        # nano /etc/keepalived/keepalived.conf

         global_defs {

            notification_email {

                [e-mail]             

            }

            notification_email_from [e-mail]

            smtp_server 192.168.60.131

            smtp_connect_timeout 30

            router_id  LVS_DEVEL_11  #与backup配置不相同的任意合法字符串

        }

 

        vrrp_instance VI_1 {

            state MASTER           #backup机器配置为BACKUP

            interface eth1            #绑定的网卡名称

            virtual_router_id 248      #必须与backup机器配置相同

            use_vmac uvmac         #名字可为任意合法字符串

            priority 200             #优先级，要比backup机器高至少50

            advert_int 1

            debug

            authentication {

               auth_type PASS       #授权类型，必须与backup相同

               auth_pass 1111        #授权密码，必须与backup相同

            }

            virtual_ipaddress {

                192.168.61.249/21    #虚拟ip地址，必须与backup相同

            }

            notify_master /usr/local/keepalived/script/vmac_tweak.sh

notify_backup /usr/local/keepalived/script/vmac_backup.sh

        }

     e）创建脚本

i ) 脚本/usr/local/keepalived/script/vmac_tweak.sh

           # mkdir /usr/local/keepalived/script

           # touch /usr/local/keepalived/script/vmac_tweak.sh

           脚本内容如下：

           #!/bin/bash

           echo  "0" > /proc/sys/net/ipv4/conf/uvmac/arp_filter

echo  "1" > /proc/sys/net/ipv4/conf/uvmac/accept_local

ii ) 脚本/usr/local/keepalived/script/vmac_backup.sh

           # mkdir /usr/local/keepalived/script

           # touch /usr/local/keepalived/script/vmac_backup.sh

           脚本内容如下：

           #!/bin/bash

           echo  "0" > /proc/sys/net/ipv4/conf/uvmac/arp_filter

echo  "0" > /proc/sys/net/ipv4/conf/uvmac/accept_local

       

  3) 启动keepalived

     # invoke-rc.d keepalived start

4) 测试keepalived

a)  MASTER启动时，查看日志/var/log/messages，显示keepalived进入MASTER状态同理，BACKUP机器将进入BACKUP状态

b)  当MASTER机器down掉时，查看BACKUP机器日志，显示keepalived进入MASTER，当MASTER重新启动时，MASTER机器进入MASTER状态而BACKUP机器keepalived重新进入BACKUP状态，此时表示keepalived安装测试已成功！