Namenode loads the filesystem state from fsimage and stays in safe mode and wait for data nodes to report their blocks. Safemode is a read-only mode for HDFS cluster, so that it does not prematurely start replicating the blocks. Use following command to let the namenode leave safemode forcefully. $ hadoop dfsadmin -safemode leave...
Apache Hadoop 3.1 have noticeable improvements any many bug fixes over the previous stable 3.0 releases. This version has many improvements in HDFS and MapReduce. This how-to guide will help you to setup Hadoop 3.1.0 Single-Node Cluster on CentOS/RHEL 7/6/5, Ubuntu 18.04, 17.10, 16.04 & 14.04, Debian 9/8/7 and LinuxMint Systems. This article has...
Apache Hadoop 2.6.5 noticeable improvements over the previous stable 2.X.Y releases. This version has many improvements in HDFS and MapReduce. This how-to guide will help you to install Hadoop 2.6 on CentOS/RHEL 7/6/5, Ubuntu and other Debian-based operating system. This article doesn’t include the overall configuration to setup Hadoop, we have only basic configuration...