lvs+keepalived實作高可用負載均衡

四台機器環境：

IP位址            lvs版本      keepalived版本     系統版本            用途

192.168.15.67      1.2.4        1.1.15            redhat4.8(64位)     MASTER

192.168.15.91      1.2.4        1.1.15            redhat4.8(64位)     BACKUP

192.168.15.93      無需安裝     無需安裝          redhat4.8(64位)     Realserver

192.168.15.94      無需安裝     無需安裝          redhat4.8(64位)     Realserver

192.168.15.120                                                        VIP

拓撲圖：

1、lvs軟體ipvsadm下載下傳安裝（主機和備機上面都必須安裝）

tar zxvf ipvsadm-1.24.tar.gz

ln -s /usr/src/kernels/2.6.9-89.EL-smp-x86_64 /usr/src/linux //注釋：這一步針對自己的系統做，否則一會安裝ipvsadm會報錯。

cd ipvsadm-1.24

make

make install

2、keepalived下載下傳安裝（主機和備機上面都必須安裝）

tar zxvf keepalived-1.1.15.tar.gz

cd keepalived-1.1.15

//注釋：如果系統rhel版本低于5.0以下安裝報錯，這裡要修改系統配置

//vi /usr/src/linux/include/linux/types.h 将下面2行紅色字型用/* */注釋掉，如下圖

/*

typedef __u16 __bitwise __sum16;

typedef __u32 __bitwise __wsum;

*/

./configure

3、将keepalived做成服務啟動（主機和備機上面都必須安裝）

cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/            注釋:拷貝服務啟動檔案

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

mkdir /etc/keepalived/                                   注釋：建立配置檔案目錄

cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/   注釋：拷貝配置檔案

cp /usr/local/sbin/keepalived /usr/sbin/                     注釋：拷貝可執行檔案

service keepalived start                                  注釋:測試服務啟動與關閉

service keepalived stop

4、主機上配置keeplived（配置前備份好keepalived.conf檔案然後再清空即可）

cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak

echo “” > /etc/keepalived/keepalived.conf

增加如下内容：

! Configuration File for keepalived

global_defs {

   notification_email {

       [email protected]

   }

   notification_email_from [email protected]

   smtp_server 127.0.0.1

   router_id LVS_DEVEL

}

vrrp_instance VI_1 {

   state MASTER                             狀态是MASTER

   interface eth0                             監聽網卡切換

   virtual_router_id 51

   priority 100                               優先級100

   advert_int 1

   authentication {

       auth_type PASS

       auth_pass 1111

virtual_ipaddress {

      192.168.15.120                          虛拟IP位址，即VIP

virtual_server 192.168.15.120 80{

   delay_loop 6

   lb_algo wlc

   lb_kind DR                                       DR模式

   persistence_timeout 1

   protocol TCP

   real_server 192.168.15.94 80{

       weight 1                                     權重，權重越高處理的請求越多

       TCP_CHECK {

       connect_timeout 1

       nb_get_retry 3

       delay_before_retry 3

       connect_port 80

       }

   real_server 192.168.15.93 80{

       weight 1

virtual_server 192.168.15.120 1099{

   lb_kind DR

   real_server 192.168.15.94 1099{

       connect_port 1099

   real_server 192.168.15.93 1099{

5、備機上配置keeplived（配置前備份好keepalived.conf檔案然後再清空即可）

增加如下内容：（隻有兩處和主機上的不一樣，下面已用紅色字型标出）

   state BACKUP                                     注意狀态是BACKUP

   interface eth0

   priority 99                                       優先級是99，比主機低

      192.168.15.120

       connect_timeout 1

6、兩台realserver上啟動腳本，腳本内容如下：

#!/bin/bash

VIP=192.168.15.120

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

case "$1" in

start)

        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

        ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up

        /sbin/route add -host $VIP dev lo:0 

        sysctl -p > /dev/null 2>&1

        echo "realserver start OK"

        ;;

stop)

        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

        ifconfig lo:0 down

        /sbin/route del $VIP > /dev/null 2>&1         

        echo "realserver stoped"

*)

        echo "Usage:$0 {start|stop}"

        exit 1

esac

exit 0

7、測試工作：

1）啟動主機和備機的keepalived服務，ip a确認是否有vip位址?

2）輸入ipvsadm -Ln檢視是否有如下内容輸出？

ipvsadm -Ln

IP Virtual Server version 1.2.0 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  192.168.15.120:80 wlc persistent 1

  -> 192.168.15.94:80             Route   1      122        4        

  -> 192.168.15.93:80             Route   1      124        6        

TCP  192.168.15.120:1099 wlc persistent 1

  -> 192.168.15.94:1099           Route   1      0          0        

  -> 192.168.15.93:1099           Route   1      0          0    

3）停止主機的keepalived服務，備機上确認是否接管vip位址？

4）備機上輸入ipvsadm -Ln檢視ActiveConn和InActConn對應的值不為0？主機上反而為0了。

5）啟動主機的keepalived服務，确認主機再次接管vip位址繼續服務？

我這裡就不做測試了！！！有問題請留言！