写在前面：如果此文有幸被某位朋友看见并发现有错的地方，希望批评指正。如有不明白的地方，愿可一起探讨。
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 -tnginx: the configuration file /etc/nginx/nginx.conf syntax is oknginx: [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.[ "$NETWORKING" = "no" ] && exit 0 nginx="/usr/sbin/nginx"prog=$(basename $nginx) NGINX_CONF_FILE="/etc/nginx/nginx.conf" [ -f /etc/sysconfig/nginx ] && . /etc/sysconfig/nginx lockfile=/var/lock/subsys/nginx make_dirs() { # make required directories user=`nginx -V 2>&1 | grep "configure arguments:" | sed 's/[^*]*--user=\([^ ]*\).*/\1/g' -` options=`$nginx -V 2>&1 | grep 'configure arguments:'` for opt in $options; do if [ `echo $opt | grep '.*-temp-path'` ]; then value=`echo $opt | cut -d "=" -f 2` if [ ! -d "$value" ]; then # echo "creating" $value mkdir -p $value && chown -R $user $value fi fi done} start() { [ -x $nginx ] || exit 5 [ -f $NGINX_CONF_FILE ] || exit 6 make_dirs echo -n $"Starting $prog: " daemon $nginx -c $NGINX_CONF_FILE retval=$? echo [ $retval -eq 0 ] && touch $lockfile return $retval} stop() { echo -n $"Stopping $prog: " killproc $prog -QUIT retval=$? echo [ $retval -eq 0 ] && rm -f $lockfile return $retval} restart() { configtest || return $? stop sleep 1 start} reload() { configtest || return $? echo -n $"Reloading $prog: " killproc $nginx -HUP RETVAL=$? 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" in start) 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 2esac
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 keepalivedglobal_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from Alexandre.Cassen@firewall.loc smtp_server 192.168.200.1 smtp_connect_timeout 30 router_id LVS_DEVEL}vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 15 priority 100 advert_int 1 authentication { auth_type PASS auth_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 keepalivedglobal_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from Alexandre.Cassen@firewall.loc smtp_server 192.168.200.1 smtp_connect_timeout 30 router_id LVS_DEVEL}vrrp_instance VI_1 { state BACKUP interface eth0 virtual_router_id 15 priority 99 advert_int 1 authentication { auth_type PASS auth_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。