[HADOOP-14818] Can not show help message of namenode/datanode/nodemanager when process started.

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 3.0.0-beta1
• Component/s: bin
• Assignee: Gergely Novák
• Reporter: Wenxin He
• Created: 30/Aug/17 07:07
• Updated: 21/Nov/17 08:35

Description

We should always get the help message whenever the process is started or not.

But now,
when datanode starts, we get an error message:

hadoop# bin/hdfs datanode -h
datanode is running as process 1701.  Stop it first.

when datanode stops, we get what we want:

hadoop# bin/hdfs --daemon stop datanode
hadoop# bin/hdfs datanode -h
Usage: hdfs datanode [-regular | -rollback | -rollingupgrade rollback ]
    -regular                 : Normal DataNode startup (default).
...

Issue Links

• is duplicated by: HDFS-12717 'hdfs namenode -help' command will not work when Namenode is Running