[
https://issues.apache.org/jira/browse/HDFS-1875?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13039455#comment-13039455
]
Matt Foley commented on HDFS-1875:
----------------------------------
Hi Eric, looks generally good. A few comments:
# MiniDFSCluster
** startDataNodes() - the "@param checkDataNodeAddrConfig" comment has been
added to the javadocs for the stubbed-out original method signature. It needs
to be associated with the new longer-args-list method signature.
# TestDFSAddressConfig
** Configuration.unset() method is only available in trunk, not yahoo-merge, at
this time. This was added to trunk in HADOOP-7001 on Nov 24, 2010, but seems
to not be in yahoo-merge. Have you asked Suresh to merge HADOOP-7001 to
yahoo-merge?
# DataNodeCluster
** In the class javadocs and/or the USAGE string, should document the change in
semantics - that the datanode addresses specified in config will be used unless
not set.
Also, with this setup, if you then run the Client on the same server as the
DataNodeCluster, can the Client communicate successfully? Or does it try to
use 127.0.0.1 and fail to connect? Have you searched for other unit test
classes that use a Client and a DataNodeCluster? Do they all still work?
Thanks.
> MiniDFSCluster hard-codes dfs.datanode.address to localhost
> -----------------------------------------------------------
>
> Key: HDFS-1875
> URL: https://issues.apache.org/jira/browse/HDFS-1875
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: test
> Affects Versions: 0.22.0
> Reporter: Eric Payne
> Assignee: Eric Payne
> Fix For: 0.23.0
>
> Attachments: HDFS-1875.patch
>
>
> When creating RPC addresses that represent the communication sockets for each
> simulated DataNode, the MiniDFSCluster class hard-codes the address of the
> dfs.datanode.address port to be "127.0.0.1:0"
> The DataNodeCluster test tool uses the MiniDFSCluster class to create a
> selected number of simulated datanodes on a single host. In the
> DataNodeCluster setup, the NameNode is not simulated but is started as a
> separate daemon.
> The problem is that if the write requrests into the simulated datanodes are
> originated on a host that is not the same host running the simulated
> datanodes, the connections are refused. This is because the RPC sockets that
> are started by MiniDFSCluster are for "localhost" (127.0.0.1) and are not
> accessible from outside that same machine.
> It is proposed that the MiniDFSCluster.setupDatanodeAddress() method be
> overloaded in order to accommodate an environment where the NameNode is on
> one host, the client is on another host, and the simulated DataNodes are on
> yet another host (or even multiple hosts simulating multiple DataNodes each).
> The overloaded API would add a parameter that would be used as the basis for
> creating the RPS sockets. By default, it would remain 127.0.0.1
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
