Hadoop's multi-node cluster starts with no namenode process? (Bloody lesson, be sure to take a snapshot)

　　Objective

When you build a Hadoop cluster, the first time you format it, take a snapshot . Do not casually lack of any process, just a format.

　　problem description : start Hadoop times NameNode uninitialized: Java.io.IOException:NameNode is notformatted.

At the same time, if you start the Namenode alone, it will appear, after startup for a while, the situation of self-disappearance.

2. Access hadoopmaster:50070 failed, indicating Namenode failed to start

　　workaround : Initialize Namenode

If you are prompted to reinitialize the Namenode, enter Y.

[Email protected] hadoop-2.6.0]$ pwd/home/hadoop/app/hadoop-2.6.0[[email protected] Hadoop  Bin/hadoop Namenode-format

　　

Shut down, then restart

[Email protected] hadoop-2.6.0]$ pwd/home/hadoop/app/hadoop-2.6.0[[email protected] Hadoop-2.6.0 ]$ sbin/stop-all.sh

sbin/start-all.sh

Cause, and finally nothing. This is a bloody lesson I have brought to everyone. Finally, again, be sure to take a snapshot!!!

Hadoop's multi-node cluster starts with no namenode process? (Bloody lesson, be sure to take a snapshot)