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案例拓扑图

安装keepalived和nginx

安装keepalived

# yum -y install keepalived

创建nginx用户组及nginx用户

# groupadd -r nginx
# useradd -g nginx -r nginx

编译安装nginx-1.4.7

# tar xf nginx-1.4.7.tar.gz
# cd nginx-1.4.7
# ./configure \--prefix=/usr \--sbin-path=/usr/sbin/nginx \--conf-path=/etc/nginx/nginx.conf \--error-log-path=/var/log/nginx/error.log \--http-log-path=/var/log/nginx/access.log \--pid-path=/var/run/nginx/nginx.pid  \--lock-path=/var/lock/nginx.lock \--user=nginx \--group=nginx \--with-http_ssl_module \--with-http_flv_module \--with-http_stub_status_module \--with-http_gzip_static_module \--http-client-body-temp-path=/usr/local/nginx/client/ \--http-proxy-temp-path=/usr/local/nginx/proxy/ \--http-fastcgi-temp-path=/usr/local/nginx/fcgi/ \--http-uwsgi-temp-path=/usr/local/nginx/uwsgi \--http-scgi-temp-path=/usr/local/nginx/scgi \--with-pcre
# make && make install

检查配置文件是否有语法错误

[root@localhost nginx-1.4.7]# nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: [emerg] mkdir() "/usr/local/nginx/client/" failed (2: No such file or directory)
nginx: configuration file /etc/nginx/nginx.conf test failed

修改错误

# mkdir /usr/local/nginx

再次检查配置文件是否有语法错误

[root@localhost nginx-1.4.7]# nginx -t

为nginx提供SysV init脚本

# vim /etc/rc.d/init.d/nginx

#!/bin/sh
#
# nginx - this script starts and stops the nginx daemon
#
# chkconfig:   - 85 15
# description:  Nginx is an HTTP(S) server, HTTP(S) reverse \
#               proxy and IMAP/POP3 proxy server
# processname: nginx
# config:      /etc/nginx/nginx.conf
# config:      /etc/sysconfig/nginx
# pidfile:     /var/run/nginx.pid# Source function library.
. /etc/rc.d/init.d/functions# Source networking configuration.
. /etc/sysconfig/network# Check that networking is up.
[ "$NETWORKING" = "no" ] && exit 0nginx="/usr/sbin/nginx"
prog=$(basename $nginx)NGINX_CONF_FILE="/etc/nginx/nginx.conf"[ -f /etc/sysconfig/nginx ] && . /etc/sysconfig/nginxlockfile=/var/lock/subsys/nginxmake_dirs() {# make required directoriesuser=`nginx -V 2>&1 | grep "configure arguments:" | sed 's/[^*]*--user=\([^ ]*\).*/\1/g' -`options=`$nginx -V 2>&1 | grep 'configure arguments:'`for opt in $options; doif [ `echo $opt | grep '.*-temp-path'` ]; thenvalue=`echo $opt | cut -d "=" -f 2`if [ ! -d "$value" ]; then# echo "creating" $valuemkdir -p $value && chown -R $user $valuefifidone
}start() {[ -x $nginx ] || exit 5[ -f $NGINX_CONF_FILE ] || exit 6make_dirsecho -n $"Starting $prog: "daemon $nginx -c $NGINX_CONF_FILEretval=$?echo[ $retval -eq 0 ] && touch $lockfilereturn $retval
}stop() {echo -n $"Stopping $prog: "killproc $prog -QUITretval=$?echo[ $retval -eq 0 ] && rm -f $lockfilereturn $retval
}restart() {configtest || return $?stopsleep 1start
}reload() {configtest || return $?echo -n $"Reloading $prog: "killproc $nginx -HUPRETVAL=$?echo
}force_reload() {restart
}configtest() {$nginx -t -c $NGINX_CONF_FILE
}rh_status() {status $prog
}rh_status_q() {rh_status >/dev/null 2>&1
}case "$1" instart)rh_status_q && exit 0$1;;stop)rh_status_q || exit 0$1;;restart|configtest)$1;;reload)rh_status_q || exit 7$1;;force-reload)force_reload;;status)rh_status;;condrestart|try-restart)rh_status_q || exit 0;;*)echo $"Usage: $0 {start|stop|status|restart|condrestart|try-restart|reload|force-reload|configtest}"exit 2
esac

赋予nginx脚本执行权限

# chmod +x /etc/rc.d/init.d/nginx

添加至服务管理列表，并让其开机自动启动

# chkconfig --add nginx
# chkconfig nginx on

提示：在两个keepalived+nginx主机上都需安装keepalkved和nginx服务

配置nginx为反向代理服务器

编辑nginx.conf配置文件

# cd /etc/nginx/
# vim nginx.conf

在nginx.conf配置文件中的http段内添加如下内容

upstream webservers {server 10.170.2.101;server 10.170.2.102;
}
server {listen 80;server_name www.muluhe.com;location / {proxy_pass http://webservers;proxy_set_header X-Real-IP $remote_addr;}
}

提示：在两台keepalived+nginx主机的nginx.conf的配置文件所添加的内容一样

配置keepalived

编辑keepalived.conf配置文件

# cd /etc/keepalived/
# vim keepalived.conf

IP地址为10.170.2.60的配置文件内容为：

! Configuration File for keepalived
global_defs {notification_email {acassen@firewall.locfailover@firewall.locsysadmin@firewall.loc}notification_email_from Alexandre.Cassen@firewall.locsmtp_server 192.168.200.1smtp_connect_timeout 30router_id LVS_DEVEL
}
vrrp_instance VI_1 {state MASTERinterface eth0virtual_router_id 15priority 100advert_int 1authentication {auth_type PASSauth_pass 111111}virtual_ipaddress {10.170.2.100}notify_master "/etc/init.d/nginx start"notify_backup "/etc/init.d/nginx stop"notify_fault "/etc/init.d/nginx stop"
}

IP地址为10.170.2.61的配置文件内容为

! Configuration File for keepalived
global_defs {notification_email {acassen@firewall.locfailover@firewall.locsysadmin@firewall.loc}notification_email_from Alexandre.Cassen@firewall.locsmtp_server 192.168.200.1smtp_connect_timeout 30router_id LVS_DEVEL
}
vrrp_instance VI_1 {state BACKUPinterface eth0virtual_router_id 15priority 99advert_int 1authentication {auth_type PASSauth_pass 111111}virtual_ipaddress {10.170.2.100}notify_master "/etc/init.d/nginx start"notify_backup "/etc/init.d/nginx stop"notify_fault "/etc/init.d/nginx stop"
}

配置web1和web2服务器

编辑web1测试页面

# vim /var/www/html/index.html
内容为：<h1>www1.muluhe.com</h1>

启动httpd服务

# /etc/init.d/httpd start

编辑web2测试页面

# vim /var/www/html/index.html
内容为：<h1>www2.muluhe.com</h1>

启动httpd服务

# /etc/init.d/httpd start

启动keepalived服务并进行测试

启动keepalived+nginx两台主机的keepalived服务

# /etc/init.d/keepalived start

在浏览器中键入10.170.2.100，刷新几下，可得到如下结果

关闭IP地址为10.170.2.60那台主机的keepalived服务

# /etc/init.d/keepalived stop

再次在浏览器中键入10.170.2.100，刷新几下，查看结果如下

由以上结果可以，keepalived实现了nginx反向代理的高可用以及nginx实现了web的负载均衡效果。