Nginx+keepalived高可用配置實戰

               

一、總體架構圖以下

二、環境準備

今天所配置的是keepalived+nginx 的負載均衡

下載keepalived軟件

[root@LB01 tools]# wget http://www.keepalived.org/software/keepalived-1.1.17.tar.gz

注意安裝前檢查內核的link文件

root@LB02 tools]# ll /usr/src/

total 8

drwxr-xr-x. 2 root root 4096 Sep 23  2011 debug

drwxr-xr-x. 3 root root 4096 Oct 19 02:03 kernels

lrwxrwxrwx. 1 root root 43 Oct 19 02:05 linux -> /usr/src/kernels/2.6.32-642.6.1.el6.x86_64/

安裝keepalived以前，安裝幾個依賴包

yum install openssl-devel -y

yum install popt* -y

而後進行編譯安裝keepalived,前面介紹了安裝過程，這裏就不演示了

./configure得出下面的結果

Keepalived configuration

------------------------

Keepalived version    : 1.1.17

Compiler         : gcc

Compiler        : -g -O2

Extra Lib      : -lpopt -lssl -lcrypto

Use IPVS Framework   : Yes

IPVS sync daemon support : Yes

Use VRRP Framework    : Yes

Use LinkWatch      : No

Use Debug flags     : No

注意./configure以後的結果，沒有錯誤就能夠了

make && make install

以後規範配置、啓動文件路徑

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

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

mkdir /etc/keepalived -p

/bin/cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/

/bin/cp /usr/local/sbin/keepalived /usr/sbin/

/etc/init.d/keepalived start

注：nginx負載均衡相關配置請參考前面的文章

LNMP架構應用實戰—Nginx反向代理負載均衡配置

三、實戰配置keepalived

[root@LB01 keepalived]# vi keepalived.conf 

! Configuration File for keepalived 

global_defs {

   notification_email {

   abc@qq.com

   }

   notification_email_from Alexandre.Cassen@firewall.loc

   smtp_server 1.1.1.1

   smtp_connect_timeout 30

   router_id LVS_3

}

vrrp_instance VI_1 {

    state MASTER

    interface eth0

    virtual_router_id 19

    priority 150

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    virtual_ipaddress {

        192.168.1.254/24

    }

}

[root@LB02 keepalived]# vi keepalived.conf

! Configuration File for keepalived

global_defs {

   notification_email {

   abc@qq.com

   }

   notification_email_from Alexandre.Cassen@firewall.loc

   smtp_server 1.1.1.1

   smtp_connect_timeout 30

   router_id LVS_6

}

vrrp_instance VI_1 {

    state BACKUP

    interface eth0

    virtual_router_id 19

    priority 100

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    virtual_ipaddress {

        192.168.1.254/24

    }

}

[root@LB01 keepalived]# /etc/init.d/keepalived start

Starting keepalived:    [  OK  ]

[root@LB02 keepalived]# /etc/init.d/keepalived start

Starting keepalived    [  OK  ]

[root@LB01 keepalived]# ip add|grep 192.168.1.254

    inet 192.168.1.254/24 scope global secondary eth0

[root@LB02 keepalived]# ip add|grep 192.168.1.254

測試訪問

代表能夠正常切換

如今咱們模擬keepalived主宕機，再測試

[root@LB01 conf]# /etc/init.d/keepalived stop

Stopping keepalived:   [  OK  ]

[root@LB02 ~]# ip add|grep 254

    inet 192.168.1.254/24 scope global secondary eth0

四、反向代理服務故障自動切換

若是實際生產環境中當keeplived主的服務器nginx服務宕機，可是主又有VIP，這時就出現沒法訪問的現象，所以能夠作以下的配置，使得這種狀況可自已切換

vi check_nginx.sh

#!/bin/sh

white true

do

PNUM=`ps -ef|grep nginx|wc -l`

#這裏也可以使用nmap 192.168.1.3 -p 80|grep open|wc -l來判斷個數

if [ $PNUM -lt 3 ];then

/etc/init.d/keepalived stop >/dec/null 2>&1

kill -9 keealived >/dec/null 2>&1

kill -9 keealived >/dec/null 2>&1

fi

sleep 5

done

sh check_nginx.sh &

啓動個守護進程進行檢查（或者加入定時任務定時執行檢查），若是nginx服務出現故障，就立馬停掉keepalived的服務，讓它自動切換到備節點上去，這樣就實現了自動切換的工做