昨天在公司内部分享了高可用负载均衡，现将环境搭建过程记录一下。

　　本文主要讲keepalived高可用，与keepalived自检的脚本。

环境：
web01： 10.8.8.51   centos7.3　　#web服务器01
web02： 10.8.8.52   centos7.3　　#web服务器02
proxy01：10.8.8.90   centos7.3    vip：10.8.8.55　　#nginx负载均衡主服务器，keepalived主服务器
proxy02：10.8.8.91   centos7.3   vip：10.8.8.55　　#nginx负载均衡备服务器，keepalived备服务器

一、web01、web02环境搭建

　　由于本文主讲keepalived高可用，环境搭建过程忽略。

　　web01、web02各自搭建一个简单的web，域名均为：www.test.com

       分别测试单机访问是否成功。

二、配置nginx负载均衡

　　在10.8.8.90和10.8.8.91主机上，分别配置nginx负载均衡。简单配置如下。分别测试负载均衡是否成功。

upstream backend {
    server 10.8.8.51:80            max_fails=3 fail_timeout=30s;
    server 10.8.8.52:80            max_fails=3 fail_timeout=30s;
}

server {
    listen     80;
    server_name  www.test.com;
    location / {
    proxy_pass http://backend;
    proxy_set_header Host   $host;
    proxy_set_header X-Forwarded-For $remote_addr;
 }
}

三、安装配置keepalived

　　keepalived官网：www.keepalived.org

　　因为是测试用，所以用最新版本：

　　下载地址：http://www.keepalived.org/software/keepalived-2.0.6.tar.gz

　　#iptables防火墙互相允许对方ip通过

 

#在proxy02机子上：
-I INPUT -s 10.8.8.90 -j ACCEPT
#在proxy01机子上：
-I INPUT -s 10.8.8.91 -j ACCEPT

 

　　1、安装keepalived

[root@proxy01 ~]# mkdir /home/tools
[root@proxy01 ~]# cd /home/tools/
[root@proxy01 tools]# wget http://www.keepalived.org/software/keepalived-2.0.6.tar.gz
[root@proxy01 tools]# tar xf keepalived-2.0.6.tar.gz 
[root@proxy01 tools]# cd keepalived-2.0.6
[root@proxy01 keepalived-2.0.6]# ./configure --prefix=/usr/local/keepalived
[root@proxy01 keepalived-2.0.6]# make
[root@proxy01 keepalived-2.0.6]# make install

　　#我的安装过lnmp环境，没有报错，如果编辑或安装时报错，先安装依赖。

yum install openssl-devel psmisc libnl* libnfnetlink-devel -y       #如果报错，就安装依赖。

　　2、配置keepalived为系统服务

　　#配置后即可使用/etc/init.d/keepalived启停keepalived服务，必须配置，在脚本中需要用到，如果使用service命令启停服务，crontab定时任务不会执行。

[root@proxy01 ~]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/
[root@proxy01 ~]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
[root@proxy01 ~]# touch /etc/init.d/keepalived
[root@proxy01 ~]# chmod +x /etc/init.d/keepalived 
[root@proxy01 ~]# vi /etc/init.d/keepalived 
#/etc/init.d/keepalived内容如下：

#!/bin/sh
#
# Startup script for the Keepalived daemon
#
# processname: keepalived
# pidfile: /var/run/keepalived.pid
# config: /etc/keepalived/keepalived.conf
# chkconfig: - 21 79
# description: Start and stop Keepalived

# Source function library
. /etc/rc.d/init.d/functions

# Source configuration file (we set KEEPALIVED_OPTIONS there)
. /etc/sysconfig/keepalived

RETVAL=0

prog="keepalived"

start() {
    echo -n $"Starting $prog: "
    daemon keepalived ${KEEPALIVED_OPTIONS}
    RETVAL=$?
    echo
    [ $RETVAL -eq 0 ] && touch /var/lock/subsys/$prog
}

stop() {
    echo -n $"Stopping $prog: "
    killproc keepalived
    RETVAL=$?
    echo
    [ $RETVAL -eq 0 ] && rm -f /var/lock/subsys/$prog
}

reload() {
    echo -n $"Reloading $prog: "
    killproc keepalived -1
    RETVAL=$?
    echo
}

# See how we were called.
case "$1" in
    start)
        start
        ;;
    stop)
        stop
        ;;
    reload)
        reload
        ;;
    restart)
        stop
        start
        ;;
    condrestart)
        if [ -f /var/lock/subsys/$prog ]; then
            stop
            start
        fi
        ;;
    status)
        status keepalived
        RETVAL=$?
        ;;
    *)
        echo "Usage: $0 {start|stop|reload|restart|condrestart|status}"
        RETVAL=1
esac

exit $RETVAL

/etc/init.d/keepalived文件内容