linux叢集 負載平衡實驗筆記

linux叢集 負載平衡實驗筆記

一、網路拓撲圖：

二、虛擬機器設定

在一台物理電腦上建立三台虛擬機器，本機為Windows作業系統，配192.168.1.0網段的地址，三台虛擬機器的作業系統都裝的CentOS5.4。其中一台做負載平衡器，這台虛擬機器需要配兩張網卡。另外兩台只要一張網卡，同時裝上httpd。

a)         負載平衡器的配置

第一張網卡配置：

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]

DEVICE=eth0

BOOTPROTO=static

BROADCAST=192.168.1.255

HWADDR=00:0C:29:57:28:8e

IPADDR=192.168.1.12

NETMASK=255.255.255.0

NETWORK=192.168.1.0

GATEWAY=192.168.1.1

ONBOOT=yes

第二張網卡配置：

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]

DEVICE=eth1

BOOTPROTO=static

BROADCAST=192.168.11.255

HWADDR=00:0C:29:57:28:89

IPADDR=192.168.11.1

NETMASK=255.255.255.0

NETWORK=192.168.11.0

ONBOOT=yes

b)         實施伺服器配置

第一台web網卡配置：

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]

DEVICE=eth0

BOOTPROTO=static

BROADCAST=192.168.1.255

HWADDR=00:0C:29:57:28:82

IPADDR=192.168.11.2

NETMASK=255.255.255.0

NETWORK=192.168.11.0

GATEWAY=192.168.11.1

ONBOOT=yes

第二台web網卡配置：

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]

DEVICE=eth0

BOOTPROTO=static

BROADCAST=192.168.1.255

HWADDR=00:0C:29:57:28:84

IPADDR=192.168.11.3

NETMASK=255.255.255.0

NETWORK=192.168.11.0

GATEWAY=192.168.11.1

ONBOOT=yes

這裡需要說明下：每個mac不同。根據實際情況填寫。如果虛擬機器的網卡啟動有問題參考：http://hi.baidu.com/wxlccsu/blog/item/f58b4acf2c09b5400eb34561.html

三、實施配置

1、在負載平衡器上

#yum –y install ipvsadm (如果有問題檢查網路或yum源)

Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
addons                                                   | 951 B     00:00
base                                                     | 2.1 kB     00:00
extras                                                   | 2.1 kB     00:00
mod-pagespeed                                            | 951 B     00:00
update                                                   | 1.9 kB     00:00
Setting up Install Process
Resolving Dependencies
There are unfinished transactions remaining. You might consider running yum-complete-transaction first to finish them.
The program yum-complete-transaction is found in the yum-utils package.
--> Running transaction check
---> Package ipvsadm.i386 0:1.24-10 set to be updated
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
Package            Arch            Version               Repository       Size
================================================================================
Installing:
ipvsadm            i386            1.24-10               base             31 k

Transaction Summary
================================================================================
Install       1 Package(s)
Upgrade       0 Package(s)

Total download size: 31 k
Downloading Packages:
ipvsadm-1.24-10.i386.rpm                                 | 31 kB     00:01
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Installing     : ipvsadm                                                  1/1

Installed:
ipvsadm.i386 0:1.24-10

Complete!

# sysctl -w net.ipv4.ip_forward=1開啟路由功能

#ipvsadm -C 清除原來的叢集策略

#ipvsadm -A -t 192.168.1.12:80 -s rr //-A 增加一個叢集，-t tcp協議，-s 演算法

#ipvsadm -L n // 查看叢集成員

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP 192.168.1.10:80 rr

#ipvsadm -a -t 192.168.1.12:80

//-a 增加一個realserver -t tcp協議的ip -m 地址偽裝叫用次數

# ipvsadm -a -t 192.168.1.12:80 -r 192.168.11.3:80 -m -w 1

#ipvsadm -L n // 再次查看叢集成員

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP 192.168.1.10:80 rr
-> 192.168.11.3:80              Masq    1      0          0
-> 192.168.11.2:80              Masq    1      0          0

或者直接設定檔

#vi/etc/sysconfig/ipvsadm
添加如下內容
-A -t 192.168.1.12:80 -s rr
-a -t 192.168.1.12:80 -r 192.168.11.2:80 -m -w 1
-a -t 192.168.1.12:80 -r 192.168.11.3:80 -m -w 1

第一條為VIP的地址以及負載平衡的演算法
-s參數為選擇負載平衡演算法
*輪叫調度（Round-RobinScheduling）RR
*加權輪叫調度（WeightedRound-RobinScheduling）WRR
*最小串連調度（Least-ConnectionScheduling）LCS
*加權最小串連調度（WeightedLeast-ConnectionScheduling）WLC
*基於局部性的最少連結（Locality-BasedLeastConnectionsScheduling）LLCS
*帶複製的基於局部性最少連結（Locality-BasedLeastConnectionswithReplicationScheduling）LLCRS
*目標地址散列調度（DestinationHashingScheduling）DHS
*源地址散列調度（SourceHashingScheduling）SHS
後面為增加各個節點
-w參數為每個節點的權值
啟動ipvsadm
#/etc/init.d/ipvsadmrestart

2、在兩台web伺服器上同時啟動httpd服務

#/etc/init.d/httpd start

在第一台

# cd /var/www/html/

#echo “this is realserv 1” > index.html

在第二台

# cd /var/www/html/

#echo “this is realserv 2” > index.html

四、測試

在Windows客戶機的瀏覽器中輸入192.168.1.12 可以看到瀏覽器先顯示” this is realserv 1”,再重新整理後顯示“this is realserv 2”

註：如果ipvsadm 是源碼的話，那就要考慮到系統核心的版本。要找到與核心版本匹配的源碼安裝包。：http://www.linuxvirtualserver.org/software/ipvs.html