Cassandra集群：一，搭建一个三节点的集群

环境准备

JDK1.8 http://download.oracle.com/otn/java/jdk/8u171-b11/512cd62ec5174c3487ac17c61aaa89e8/jdk-8u171-linux-x64.tar.gz

Cassandra 2.1.* http://archive.apache.org/dist/cassandra/2.1.20/apache-cassandra-2.1.20-bin.tar.gz

Host Name	IP Address	OS
sht-sgmhadoopcm-01	172.16.101.54	CentOS7.1
sht-sgmhadoopnn-01	172.16.101.55	CentOS7.1
sht-sgmhadoopnn-02	172.16.101.56	CentOS7.1