Exception in thread “main” org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /testtxt. could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and 1 node(s) are excluded in this operation.

Issue: When you upload a file to HDFS, you may encounter following exception. Exception: Exception in thread “main” org.apache.hadoop.ipc.RemoteException(java.io.IOException): File /testtxt. could only be replicated to 0 nodes instead of... Read More | Share it now!

在EC2上创建root用户,并使用root用户登录

今天开始研究亚马逊的云主机EC2,遇到了一个问题,我需要在EC2上安装tomcat,但是yum命令只能是root用户才可以运行,而EC2默认是以ec2-user用户登录的,所以需要切换到root用户登录,特将研究成果公布如下:   1、根据官网提供的方法登录连接到EC2服务器(官网推荐windows用户使用PUTTY连接) 2、... Read More | Share it now!