Nginx+keepalived主从双机热备自动切换解决方案

xiayu

Nginx+keepalived主从双机热备自动切换解决方案

测试环境如下：
系统：Ceentos 6.4 64位
主nginx服务器：192.168.122.5
备nginx服务器：192.168.122.6
VIP：192.168.122.15
一、Nginx+keepalived 安装—脚本安装

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 #!/bin/bash # author: kuangl # mail: kuangl@orient-media.com # description: The installation of Nginx files. # -------------------------------------------------------- # ## Nginx_install # -------------------------------------------------------- # # Nginx installation #CURRENT_PATH=$(pwd) for i in $(rpm -q gcc gcc-c++ kernel-devel openssl-devel zlib-devel popt-devel popt-static libnl-devel wget make |grep 'not installed' | awk '{print $2}') do yum -y install $i done [ -d /root/software ] [ "$?" != 0 ] && mkdir /root/software cd /root/software [ !-e pcre-8.33.tar.gz ] && wget ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-8.33.tar.gz tar -zxvf pcre-8.33.tar.gz cd pcre-8.33 ./configure make && make install echo $? || [ $? != 0] || echo" installation pcrefailed" || exit 1 cd /root/software [ ! -e nginx-1.2.9.tar.gz ] && wget http://nginx.org/download/nginx-1.2.9.tar.gz tar -zxvf nginx-1.2.9.tar.gz cd nginx-1.2.9 ./configure--prefix=/usr/local/nginx --with-http_ssl_module --with-http_sub_module --with-http_stub_status_module--with-http_gzip_static_module make && make install echo $? || [ $? != 0] || echo" installationnginxfailed" || exit 1 # -------------------------------------------------------- # ## Keepalived_intsall # -------------------------------------------------------- # # Keepalived installation cd /root/softwarae [ ! -e keepalived-1.2.4.tar.gz ] &&wget http://www.keepalived.org/software/keepalived-1.2.4.tar.gz tar -zxvf keepalived-1.2.4.tar.gz cd keepalived-1.2.4 ln -s /usr/src/kernels/$(uname -r) /usr/src/kernels/linux ./configure --prefix=/usr--bindir=/usr/bin--sbindir=/usr/bin--libexecdir=/usr/libexec --localstatedir=/var --libdir=/lib64--infodir=/usr/share/info--sysconfdir=/etc --mandir=/usr/local/share/man--with-kernel-dir=/usr/src/kernels/linux make && make install echo $? || [ $? != 0] || print " installation keepalivedfailed" || exit 1 chkconfig --add keepalived chkconfig --level 345 keepalived on

二、主Nginx 配置

1 2 3 [iyunv@node5 conf]# mkdir -p /var/www/html [iyunv@node5 conf]# cat "192.168.122.5" > /var/www/html/index.html [iyunv@node5 conf]# vim nginx.conf 1 2 3 [iyunv@node5 conf]# ../sbin/nginx -s reload [iyunv@node5 conf]# curl http://192.168.122.5 192.168.122.5

 
三、主Keepalived配置

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 [iyunv@node6 conf]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { 404060@qq.com 138162@139.com } notification_email_from 404060@qq.com smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_nginx { script "/etc/keepalived/chk_nginx.keepalived.sh" interval 2 weight 2 } vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 51 priority 200 advert_int 1 authentication { auth_type PASS auth_pass kuangling } track_script { chk_nginx.keepalived } virtual_ipaddress { 192.168.122.15 } }

 
四、备nginx配置

1 2 3 [iyunv@node6 conf]# mkdir -p /var/www/html [iyunv@node6 conf]# cat "192.168.122.6" > /var/www/html/index.html [iyunv@node6 conf]# vim nginx.conf 1 2 3 [iyunv@node6 conf]# ../sbin/nginx -s reload [iyunv@node6 conf]# curl http://192.168.122.6 192.168.122.6

五、备keepalived配置

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 [iyunv@node6 conf]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { 404060@qq.com 138162@139.com } notification_email_from 404060@qq.com smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_nginx { script "/etc/keepalived/chk_nginx.keepalived.sh" interval 2 weight 2 } vrrp_instance VI_1 { state BACKUP interface eth0 virtual_router_id 51 priority 150 advert_int 1 authentication { auth_type PASS auth_pass kuangling } track_script { chk_nginx.keepalived } virtual_ipaddress { 192.168.122.15 } }

六、分别在2台nginx服务器上添加检测脚本：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 [iyunv@node6 conf]# vim /etc/keepalived/chk_nginx.keepalived.sh #!/bin/bash # description: # 定时查看Nginx是否存在，如果不存在则启动Nginx # 如果启动失败，则停止keepalived status=`ps -C nginx --no-header |wc -l` if [ $status -eq 0 ];then /usr/local/nginx/sbin/nginx sleep 3 if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then killall keepalived fi fi [iyunv@node6 conf]#chmod +x /etc/keepalived/chk_nginx.keepalived.sh

七、测试
分别在2台nginx上启动nginx和keepalived服务，然后分别用ip a 查看ip
 
 
 
本文出自 “&思远晨曦” 博客，请务必保留此出处http://kling.blog.iyunv.com/3320545/1240359
 
 
nginx+keepalived实现双机热备的高可用
64人收藏此文章, 我要收藏发表于15天前(2013-09-12 23:11) , 已有664次阅读 ，共1个评论

目录：[ - ]

• keepalived安装
  
• keepalived的配置
  
• keepalived的测试
  

这篇文章简单介绍利用keepalived软件，实现对nginx服务器的高可用，即实现故障自动切换。假设你已经安装好nginx，下面介绍keepalived的安装和使用。
keepalived安装

• yum install openssl-devel
  
• cd /tmp
  
• wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
  
• tar xzf keepalived-1.2.2.tar.gz
  
• cd keepalived-1.2.2
  
• ./configure
  
• make && make install
  
• cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/
  
• cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
  
• chmod +x /etc/init.d/keepalived
  
• chkconfig --add keepalived
  
• chkconfig keepalived on
  
• mkdir /etc/keepalived
  
• ln -s /usr/local/sbin/keepalived /usr/sbin/
  

keepalived的配置
更详细的keepalived配置文件说明可以执行man keepalived.conf查看。
我们假设主服务器IP:192.168.1.103,从服务器ip:192.168.1.101 虚拟ip:192.168.1.110
下面对主服务器的keepalived进行配置：

• vi /etc/keepalived/keepalived.conf
  

• global_defs {
  
•    notification_email {
  
•      admin@centos.bz
  
•    }
  
•    notification_email_from keepalived@domain.com
  
•    smtp_server 127.0.0.1
  
•    smtp_connect_timeout 30
  
•    router_id LVS_DEVEL
  
• }
  
• vrrp_script chk_http_port {
  
•                 script "/opt/nginx_pid.sh"
  
•                 interval 2
  
•                 weight 2
  
• }
  
• vrrp_instance VI_1 {
  
•     state MASTER        ############ 辅机为 BACKUP
  
•     interface eth0
  
•     virtual_router_id 51
  
•     mcast_src_ip 192.168.1.103
  
•     priority 102                  ########### 权值要比 back 高
  
•     advert_int 1
  
•     authentication {
  
•         auth_type PASS
  
•         auth_pass 1111
  
•     }
  
• track_script { 
  
•         chk_http_port ### 执行监控的服务 
  
•         }
  
•     virtual_ipaddress {
  
•        192.168.1.110
  
•     }
  
• }
  

从服务器：

• global_defs {
  
•    notification_email {
  
•      admin@centos.bz
  
•    }
  
•    notification_email_from keepalived@domain.com
  
•    smtp_server 127.0.0.1
  
•    smtp_connect_timeout 30
  
•    router_id LVS_DEVEL
  
• }
  
• vrrp_script chk_http_port {
  
•                 script "/opt/nginx_pid.sh"
  
•                 interval 2
  
•                 weight 2
  
• }
  
• vrrp_instance VI_1 {
  
•     state BACKUP
  
•     interface eth0
  
•     virtual_router_id 51
  
•     mcast_src_ip 192.168.1.101
  
•     priority 101              ##########权值 要比 master 低。。
  
•     advert_int 1
  
•     authentication {
  
•         auth_type PASS
  
•         auth_pass 1111
  
•     }
  
• track_script { 
  
•         chk_http_port ### 执行监控的服务 
  
•         }
  
•     virtual_ipaddress {
  
•        192.168.1.110
  
•     }
  
• }
  

之后分别在主从服务器建立nginx的监控脚本：

• vi /opt/nginx_pid.sh
  

• #!/bin/bash
  
• A=`ps -C nginx --no-header |wc -l`               
  
• if [ $A -eq 0 ];then                                       
  
•                 /usr/local/nginx/sbin/nginx
  
•                 sleep 3
  
•                 if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then
  
•                        killall keepalived
  
•                 fi
  
• fi
  

然后分别启动主从服务器的keepalived:

• service keepalived start
  

keepalived的测试
我们在主服务器上执行命令ip a，显示如下：

• 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
  
•     link/ether 00:0c:29:aa:a1:e4 brd ff:ff:ff:ff:ff:ff
  
•     inet 192.168.1.103/24 brd 255.255.255.255 scope global eth0
  
•     inet 192.168.1.110/32 scope global eth0
  

证明主服务器已经绑定了虚拟ip 192.168.1.110
在从服务器上执行命令ip a,显示如下：

• 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
  
•     link/ether 00:0c:29:2b:94:3b brd ff:ff:ff:ff:ff:ff
  
•     inet 192.168.1.101/24 brd 255.255.255.255 scope global eth0
  

显示表明从服务器上没有绑定vip 192.168.1.110,只有本机真实ip192.168.1.101
下面我们停止主服务器的nginx进程，再看看ip绑定情况:
主服务器的情况：

• 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
  
•     link/ether 00:0c:29:aa:a1:e4 brd ff:ff:ff:ff:ff:ff
  
•     inet 192.168.1.103/24 brd 255.255.255.255 scope global eth0
  

从服务器的情况：

• 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
  
•     link/ether 00:0c:29:2b:94:3b brd ff:ff:ff:ff:ff:ff
  
•     inet 192.168.1.101/24 brd 255.255.255.255 scope global eth0
  
•     inet 192.168.1.110/32 scope global eth0
  

由此可见vip已经指向了从服务器。