①环境：
Linux :CentOs 6.5
②安装：
a. 因为ElasticSearch最新版5.3需要内核3.5以上，所以我选择了ElasticSearch 2.4.1，但是要使用ES必须保证Java jdk.1.8版本,而centos 6.x默认版本为jdk,1.7 所以，首先要升级java到1.8
下载地址为：http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
wget http://download.oracle.com/otn-pub/java/jdk/8u121-b13/e9e7ea248e2c4826b92b3f075a80e441/jdk-8u121-linux-x64.rpm
cd /usr/local/src
wget https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.4.1/elasticsearch-2.4.1.rpm --no-check-certificate
