（在搭建Spark集群之前要先搭建Hadoop集群哦）
教程链接：CentOS7 搭建Spark集群环境
补充 问题一scp -c /usr/local/spark/* root@node1:/usr/local/spark
复制不起作用
解决办法：将-c改为-r，即
scp -r /usr/local/spark/* root@node1:/usr/local/spark
./start-all.sh之后出现
node1: ssh: Could not resolve hostname node1: Name or service not known
解决办法：
参考：ssh: Could not resolve hostname node1: Name or service not known
