keepalived + haproxy 實現web 雙主模型的高可用負載平衡

標籤：haproxy 雙主模型 高可用負載平衡 keepalived

1、本文的架構圖：

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M00/25/90/wKioL1Nki0jiTqeUAAE35qbWq7g043.jpg" title="haproxy、keepalived.png" alt="wKioL1Nki0jiTqeUAAE35qbWq7g043.jpg" />

闡述各伺服器用途：

   1、haproxy在本構架中實現的是：負載平衡

   2、keepalived實現對haproxy的高可用

   3、apache static 實現靜態頁面的訪問

   4、aoache dynamic實現動態網頁面的訪問，圖中有兩個是實現負載平衡的

配置各功能模組：

   一、配置haproxy和keepalived

驗證：

        1、當一台keepalived宕機後，VIP會不會轉移到另外一台伺服器

        2、當一台haproxy服務出故障，VIP會不會轉移到另外一台伺服器

注意：

        那如果keepalived宕機了，haproxy服務還正常運行，我們要不要讓另外一台伺服器把VIP奪過去呢？

        理論上來講：最好不要，但是我們的keepalived中的指令碼監控著haproxy的進程，keepalived宕機之後，就無從得知haproxy的健康狀態，也不能決定自己的優先權priority降不降低了。所以，理論上來講最好不要，但是實際中光靠keepalived是做不到的。

配置：

1、給兩台伺服器分別安裝上keepalived

[[email protected] ~]# yum -y install keepalived

2、配置keepalived

[[email protected] ~]# vim /etc/keepalived/keepalived.conf! Configuration File for keepalivedglobal_defs {   notification_email {        [email protected]    佈建服務狀態變化發送郵件到哪個地址   }   notification_email_from [email protected]   smtp_server 127.0.0.1    給哪個smtp伺服器發郵件   smtp_connect_timeout 30    聯絡上面smtp伺服器30秒聯絡不上，就逾時   router_id LVS_DEVEL}vrrp_script chk_haproxy {     本指令碼是用來檢測該伺服器上haproxy服務的健康狀態的    script "killall -0 haproxy"    interval 1    weight -2}vrrp_instance VI_1 {    state MASTER   這太伺服器為主的keepalived    interface eth0    通過eth0網卡廣播    virtual_router_id 200  虛擬路由id要改，如果在一個區域網路中有多個keepalived叢集    priority 100   優先順序    advert_int 1    authentication {        auth_type PASS        auth_pass 11112222    }    track_script {        chk_haproxy    }    virtual_ipaddress {        192.168.1.200   原生虛擬IP   }    notify_master "/etc/keepalived/notify.sh master" 各不用狀態下啟動並執行指令碼    notify_backup "/etc/keepalived/notify.sh backup"    notify_fault "/etc/keepalived/notify.sh fault"}vrrp_instance VI_2 {   另外一台主keepalived的從    state BACKUP    interface eth0    virtual_router_id 57    priority 99   設定要比另外一台主keepalived的優先順序低    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    track_script {        chk_mantaince_down   }    virtual_ipaddress {        192.168.1.201   }}

3、寫keepalived處在不同狀態下所啟動並執行指令碼

#!/bin/bash# Author: MageEdu <[email protected]># description: An example of notify script#vip=192.168.1.200contact=‘[email protected]‘notify() {    mailsubject="`hostname` to be $1: $vip floating"    mailbody="`date ‘+%F %H:%M:%S‘`: vrrp transition, `hostname` changed to be $1"    echo $mailbody | mail -s "$mailsubject" $contact}                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  case "$1" in    master)        notify master        /etc/rc.d/init.d/haproxy start        exit 0    ;;    backup)        notify backup        /etc/rc.d/init.d/haproxy stop        exit 0    ;;    fault)        notify fault        /etc/rc.d/init.d/haproxy stop        exit 0    ;;    *)        echo ‘Usage: `basename $0` {master|backup|fault}‘        exit 1    ;;esac給指令碼以執行許可權：chmod  +x  /etc/keepalived/notify.sh

4、配置haproxy

   因為要實現動靜分離，那麼我們在設定檔中，就要定義動態資源靜態資源轉移到不同的服務上去

[[email protected] ~]# yum -y install haproxy  安裝haproxy[[email protected] ~]# vim /etc/haproxy/haproxy.cfg    #    log         127.0.0.1 local2    chroot      /var/lib/haproxy    pidfile     /var/run/haproxy.pid    maxconn     4000    user        haproxy    group       haproxy    daemon    # turn on stats unix socket    stats socket /var/lib/haproxy/stats#---------------------------------------------------------------------# common defaults that all the ‘listen‘ and ‘backend‘ sections will# use if not designated in their block#---------------------------------------------------------------------defaults    mode                    http      指定haproxy工作模式為http    log                     global    option                  httplog    option                  dontlognull    option http-server-close       當用戶端逾時時，允許服務端中斷連線    option forwardfor       except 127.0.0.0/8  在http的回應標頭部加入forwardfor    option                  redispatch    #在使用了基於cookie的會話保持的時候，通常加這麼一項，一旦後端某一server宕機時，能夠將其會話重新派發到其它的upstream servers    retries                 3    timeout http-request    10s    timeout queue           1m    timeout connect         10s    timeout client          1m    timeout server          1m    timeout http-keep-alive 10s    timeout check           10s    maxconn                 3000#---------------------------------------------------------------------# main frontend which proxys to the backends#---------------------------------------------------------------------frontend  main *:80  前端代理    acl url_static       path_beg       -i /static /images /javascript /stylesheets    acl url_static       path_end       -i .jpg .gif .png .css .js    acl url_dynamic      path_end       -i .php    use_backend static          if url_static    default_backend             dynamic#---------------------------------------------------------------------# static backend for serving up images, stylesheets and such#---------------------------------------------------------------------backend static   後端的靜態請求響應    balance     roundrobin    server      static 192.168.1.100:80 inter 3000 rise 2 fall 3 check maxconn 5000#---------------------------------------------------------------------# round robin balancing between the various backends#---------------------------------------------------------------------backend dynamic   後端的動態請求響應    balance     roundrobin    server  dynamic1 192.168.1.101:80 inter 3000 rise 2 fall 3 check maxconn 5000    server  dynamic2 192.168.1.102:80 inter 3000 rise 2 fall 3 check maxconn 5000listen statistics        mode http        bind *:8080~       stats enable        stats auth admin:admin        stats uri /admin?stats   指定URI的訪問路徑        stats admin if TRUE        stats hide-version        stats refresh 5s        acl allow src 192.168.0.0/24   定義存取控制清單        tcp-request content accept if allow        tcp-request content reject

5、配置另外一台haproxy伺服器

   因為兩台伺服器的配置大體相同，我們就直接講以上配置好的複製檔案和指令檔都傳到這台haproxy伺服器上，做下修就可以了

[[email protected] ~]# scp /etc/keepalived/keepalived.conf [email protected]:/etc/keepalived/[email protected]‘s password:keepalived.conf                                                                               100% 4546     4.4KB/s   00:00 [[email protected] ~]# scp /etc/keepalived/notify.sh [email protected]:/etc/keepalived/[email protected]‘s password:notify.sh                                                                                     100%  751     0.7KB/s   00:00 [[email protected] ~]# scp /etc/haproxy/haproxy.cfg [email protected]:/etc/haproxy/[email protected]‘s password:haproxy.cfg                                                                                   100% 3529     3.5KB/s   00:00

    傳輸完成，接著來配置 /etc/keepalived/keepalived.conf  因為兩個節點上的/etc/haproxy/haproxy.cfg相同不用更改

    interface eth0! Configuration File for keepalivedglobal_defs {   notification_email {        [email protected]   }   notification_email_from [email protected]   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id LVS_DEVEL}vrrp_script chk_haproxy {    script "killall -0 haproxy"    interval 1    weight -2}vrrp_instance VI_1 {    state BACKUP      這台把master改成 backup    interface eth0    virtual_router_id 200    priority 99       優先順序調的比上一個低    advert_int 1    authentication {        auth_type PASS        auth_pass 11112222    }    track_script {        chk_haproxy    }    virtual_ipaddress {        192.168.1.200   }}vrrp_instance VI_2 {    state MASTER      本台的這個要調成MASTER，上個是backup    interface eth0    virtual_router_id 57    priority 100    這個優先順序也要高於上個    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        192.168.1.201   }    notify_master "/etc/keepalived/notify.sh master"    notify_backup "/etc/keepalived/notify.sh backup"    notify_fault "/etc/keepalived/notify.sh fault"}

注意：

notify_master "/etc/keepalived/notify.sh master" notify_backup "/etc/keepalived/notify.sh backup"

notify_fault "/etc/keepalived/notify.sh fault"

3個狀態分別要執行的指令碼，只能放在 MASTER中，原因是：因為是互為主從，每個主的都會有個另外一個主的從，如果

把這 “3個狀態執行指令碼” 寫入到從的地區中，那麼另外一個主的從狀態就會執行這個指令碼，因為就會停掉所要高可用的

程式，這就造成了，兩個VIP全部轉移到其中一個伺服器上去。

我們來驗證下，如果keepalived和haproxy分別宕機，vip會不會轉移：

   在兩個節點上都啟動 keepalived和haproxy服務

[[email protected] ~]# service haproxy startStarting haproxy:                                          [  OK  ][[email protected] ~]# service keepalived startStarting keepalived:                                       [  OK  ]

以下為正常情況：

keepalived 1：

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M00/25/90/wKiom1Nkl9uBLSLkAAI7Nv82x7o994.jpg" title="111.png" alt="wKiom1Nkl9uBLSLkAAI7Nv82x7o994.jpg" />

keepalived 2：

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/90/wKioL1Nkl--RJs-GAAHu-Fe95vg162.jpg" title="222.jpg" alt="wKioL1Nkl--RJs-GAAHu-Fe95vg162.jpg" />

我們來類比讓第一個haproxy停止掉，再看下，VIP會不會全到 keepalived 2上面去：

[[email protected] ~]# service haproxy stopStopping haproxy:                                          [  OK  ]

查看keepalived 1 和 keepalived 2

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M01/25/91/wKioL1NksZLBURk8AAH68TIiVaw151.jpg" title="11111.png" alt="wKioL1NksZLBURk8AAH68TIiVaw151.jpg" />

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKioL1NksbmgAwBPAAGZbYr2wF4250.jpg" title="111111.png" alt="wKioL1NksbmgAwBPAAGZbYr2wF4250.jpg" />

   看，都過來了。。。。

驗證負載平衡很動靜分離

   我們給3個web服務不同的網頁

   1、給apache static一個靜態頁面，來驗證如果請求的不是以 .php結尾的網頁檔案都定向到這太伺服器上來

   2、給apache dynamic 1 、2 分別兩個 index.php ，實現對動態網頁的負載平衡

我們給apache static 一個符合-i .jpg .gif .png .css .js的網頁，就給個圖片網頁吧

apache static

scp 1.png [email protected]:/var/www/html

apache dynamic 1

vim /var/www/html/index.php192.168.1.101<?php    phpinfo();?>

 apache dynamic 2

vim /var/www/html/index.php192.168.1.102<?php    phpinfo();?>

1、我們來請求 1.png 結尾的靜態檔案

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKiom1Nkw6uDu_vyAAHCiPEKG6g430.jpg" title="static.png" alt="wKiom1Nkw6uDu_vyAAHCiPEKG6g430.jpg" />

2、我們來請求 .php結尾的頁面

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKioL1NkxHDg_K8DAAFLVYOf_d4414.jpg" title="dh.png" alt="wKioL1NkxHDg_K8DAAFLVYOf_d4414.jpg" />

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M00/25/91/wKioL1NkxIfym9afAAE52TC8wJ8462.jpg" title="dh2.png" alt="wKioL1NkxIfym9afAAE52TC8wJ8462.jpg" />

   如此看來，已經對以.php的動態網頁面做了負載平衡了

   我們再通過 192.168.1.201 這個虛擬 ip 訪問試試：

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M00/25/91/wKiom1NkxeKzjSWPAAFM55WLzgs165.jpg" title="dh.png" alt="wKiom1NkxeKzjSWPAAFM55WLzgs165.jpg" />

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKioL1Nkxe-jm0ZaAAEqNN02zgU592.jpg" title="dh.png" alt="wKioL1Nkxe-jm0ZaAAEqNN02zgU592.jpg" />

由此看來，也實現了雙主模型了，兩個haproxy同時可以服務了。。。

3、我們來看看狀態頁面

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKiom1Nkx9_B57xfAAEctjJMZnc262.jpg" title="dh.png" alt="wKiom1Nkx9_B57xfAAEctjJMZnc262.jpg" />

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M01/25/91/wKioL1Nkx8nz0IfTAAEa74C_zWI937.jpg" title="dh2.png" alt="wKioL1Nkx8nz0IfTAAEa74C_zWI937.jpg" />

650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/25/91/wKioL1Nkx9iAeZsaAAeekRUkLfg471.jpg" title="dh1.png" alt="wKioL1Nkx9iAeZsaAAeekRUkLfg471.jpg" />

本文出自 “linux營運” 部落格，請務必保留此出處http://xz159065974.blog.51cto.com/8618592/1405812