Nginx+keepalived 脚本安装主从双机热备自动切换解决方案

Nginx+keepalived 脚本安装主从双机热备自动切换解决方案

2013-07-02 19:24:13

标签：filesnginx keepalived

原创作品，允许转载，转载时请务必以超链接形式标明文章 原始出处 、作者信息和本声明。否则将追究法律责任。http://kling.blog.51cto.com/3320545/1240359

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: [e-mail] # 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 wgetmake |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 ] && wgetftp://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 [root@node5 conf]# mkdir -p /var/www/html [root@node5 conf]# cat "192.168.122.5" > /var/www/html/index.html [root@node5 conf]# vim nginx.conf 1 2 3 [root@node5 conf]# ../sbin/nginx -s reload [root@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 [root@node6 conf]# vim /etc/keepalived/keepalived.conf ! Configuration Filefor keepalived global_defs { notification_email { [e-mail] [e-mail] } notification_email_from [e-mail] 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 [root@node6 conf]# mkdir -p /var/www/html [root@node6 conf]# cat "192.168.122.6" > /var/www/html/index.html [root@node6 conf]# vim nginx.conf 1 2 3 [root@node6 conf]# ../sbin/nginx -s reload [root@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 [root@node6 conf]# vim /etc/keepalived/keepalived.conf ! Configuration Filefor keepalived global_defs { notification_email { [e-mail] [e-mail] } notification_email_from [e-mail] 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 [root@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 [root@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.51cto.com/3320545/1240359

注：

1.这篇文章是keepalived单主高可用配置

2.keepalived没有解决自身故障的问题，更多是针对操作系统和网络故障来进行vip迁移

3.keepalived没有和nginx联动，也就是说nginx故障的情况下，keepalived不会知道，也就不会迁移vip，这个问题的解决方法：将监控脚步长期在后台持续运行（while无限循环，sleep 1）

脚步改造如下：

#!/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

while [ a==a ]

do

status=`ps -C nginx --no-header |wc -l`

if [ $status -eq 0 ];then

/usr/local/nginx/sbin/nginx > /dev/null 2>&1

sleep 3

if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then

killall keepalived > /dev/null 2>&1

fi

fi

sleep 1

done