Lvs+keepalived 高可用性負載均衡自動化配置

Lvs+keepalived 高可用性負載均衡配置

       前言* 隨着互聯網的發展，提供用戶訪問的web服務器，必需要保證天天24不間斷服務，訪問量不斷增長，有什麼好的web架構既能實現高可用性負載均衡，並且價格又是免費的呢？答案有木有？有！lvs+keepalived 是不錯的選擇！

 

1、實驗環境：4臺centos 5.4 ，以及簡單的拓撲圖：

LVS-Master 192.168.2.108

LVS-BACKUP 192.168.2.109

LVS-DR-VIP    192.168.2.100

WEB1-Realserver 192.168.2.79

WEB2-Realserver  192.168.2.80

 

 

2、安裝ipvsadm+keepalived,用腳本自動安裝：

 

因爲咱們使用的是lvs+keepalived，因此這裏不須要配置lvs-dr腳本，直接在keepalived.conf裏面配置便可！

#!/bin/sh

###腳本編寫目的:自動安裝lvs+keepalived

###編寫時間: 2011 年7月6日17:25:39

###初稿人:wugk

###定義變量

DIR1=/usr/src   

DIR2=/usr/local

 

cat << EOF

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

++++Welcome to use Linux installed a key LVS+KEEPALIVED shells scripts

+++++++++++++++++++++*************************++++++++++++++++++++++++

EOF

 

if

[ $UID -ne 0 ];then

 

echo 「This script must use root user ,please exit……」

sleep 2

exit 0

 

fi

 

download ()

{

cd $DIR1 && wget -c http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.24.tar.gz http://www.keepalived.org/software/keepalived-1.1.15.tar.gz

 

if

[ $? = 0 ];then

 

echo "Download LVS Code is OK!"

else

echo "Download LVS Code is failed,Please check!"

exit 1

fi

}

 

ipvsadm_install ()

{

 

ln -s $DIR1/kernels/2.6.* $DIR1/linux

 

cd $DIR1 && tar xzvf ipvsadm-1.24.tar.gz &&cd ipvsadm-1.24 && make && make install

if

[ $? -eq 0 ];then

echo "Install ipvsadm success,please waiting install keepalived ..............."

else

echo "Install ipvsadm failed ,please check !"

exit 1

fi

}

 

keepalived_install ()

{

cd $DIR1 && tar -xzvf keepalived-1.1.15.tar.gz &&cd keepalived-1.1.15 && ./configure && make && make install

if

[ $? -eq 0 ];then

echo "Install keepalived success,please waiting configure keepalived ..............."

else

echo "Install keepalived failed ,please check install version !"

exit 1

fi

}

 

######若是以上軟件包編譯報錯的話，請檢查相關的版本跟系統版本之間的關係，而後手動下載安裝.

 

keepalived_config ()

{

cp $DIR2/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/ && cp $DIR2/etc/sysconfig/keepalived /etc/sysconfig/ && mkdir -p /etc/keepalived &&cp $DIR2/etc/keepalived/keepalived.conf /etc/keepalived/ && cp $DIR2/sbin/keepalived /usr/sbin/

if

[ $? -eq 0 ];then

 

echo "Keepalived system server config success!"

else

echo "Keepalived system server config failed ,please check keepalived!"

exit 1

fi

 

}

 

PS3="Please select Install Linux Packages:"

 

select option in download ipvsadm_install keepalived_install keepalived_config

 

do

 

$option

 

done

以上腳本分別在lvs-master和lvs-backup上執行安裝。

 

3、配置keepalived.conf：內容以下是lvs-master配置

也能夠參考配置： http://chinaapp.sinaapp.com/download/keepalived.conf 能夠直接打開

 

! Configuration File for keepalived

 

global_defs {

   notification_email {

      wgkgood@163.com

   }

   notification_email_from wgkgood@163.com

   smtp_server 127.0.0.1

   smtp_connect_timeout 30

   router_id LVS_DEVEL

}

 

# VIP1

vrrp_instance VI_1 {

    state MASTER  

    interface eth0

    lvs_sync_daemon_inteface eth0

    virtual_router_id 51

    priority 100

    advert_int 5

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    virtual_ipaddress {

        192.168.2.100  

    }

}

#REAL_SERVER_1

virtual_server 192.168.2.100 80 {

    delay_loop 6   

    lb_algo wlc   

    lb_kind DR  

    persistence_timeout 60   

    protocol TCP        

 

    real_server 192.168.2.79 80 {

        weight 100       

        TCP_CHECK {

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

        }

}

#REAL_SERVER_2

    real_server 192.168.2.80 80 {

        weight 100

        TCP_CHECK {

        connect_timeout 10

        nb_get_retry 3

        delay_before_retry 3

        connect_port 80

       

        }

    }

}

注意***Lvs-backup端一樣配置，只須要更改state MASTER爲state BACKUP，修改priority 100爲priority 90便可。

 

4、分別在web一、web2上配置好apache，而後分別執行以下腳本：

 

以下的VIP1指的是lvs-dr-vip地址，及對外提供訪問的虛擬ip：

#!/bin/sh

 

PS3="Please Choose whether or not to start a realserver VIP1 configuration:"

 

select i in "start" "stop"

 

do

case "$i" in

 

start)

 

read -p "Please enter the virtual server IP address:" VIP1

ifconfig lo:0 $VIP1 netmask 255.255.255.255 broadcast $VIP1

/sbin/route add -host $VIP1 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

sysctl -p >/dev/null 2>&1

echo "RealServer Start OK"

exit 0

;;

 

stop)

ifconfig lo:0 down

route del $VIP1 >/dev/null 2>&1

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 "RealServer Stoped"

exit 1

;;

*)

echo "Usage: $0 {start|stop}"

exit 2

esac

done

腳本會提示是否啓動，按1即啓動，而後輸入vip地址 192.168.2.100 ，用ifconfig你會看到：lo:0的ip即表示配置ip成功。

lo:0       Link encap:Local Loopback 

          inet addr:192.168.2.100 Mask:255.255.255.255

          UP LOOPBACK RUNNING MTU:16436 Metric:1

 

5、最後啓動lvs-master、lvs-backup上面的keepalived服務便可：

/etc/init.d/keepalived restart 查看lvs-master日誌：

 

在瀏覽器裏面訪問 http://192.168.2.100/ 便可！當你宕掉lvs-master後，lvs-backup會接管變成lvs-master提供服務，當lvs-master故障恢復後，lvs-backup又會變成原來的狀態！

所安裝的腳本能夠在這裏下載：

 

http://chinaapp.sinaapp.com/download/lvs-keepalived.sh         在lvs-master和lvs-backup上執行  

 

http://chinaapp.sinaapp.com/download/realserver.sh                 在web服務器端執行       

本文出自 「【煙雨樓臺】」 博客，請務必保留此出處http://wgkgood.blog.51cto.com/1192594/605322