You are viewing a plain text version of this content. The canonical link for it is here.

Posted to hdfs-dev@hadoop.apache.org by "Bernd Fondermann (JIRA)" <ji...@apache.org> on 2013/08/27 13:18:51 UTC

[jira] [Created] (HDFS-5133) Datanodes without reverse DNS cannot be added to Nameserver

Bernd Fondermann created HDFS-5133:
--------------------------------------

             Summary: Datanodes without reverse DNS cannot be added to Nameserver
                 Key: HDFS-5133
                 URL: https://issues.apache.org/jira/browse/HDFS-5133
             Project: Hadoop HDFS
          Issue Type: Bug
          Components: namenode
    Affects Versions: 2.1.0-beta
            Reporter: Bernd Fondermann


I've a test cluster in a 10.x.y.z net.
When datanodes (on a different machine from the namenode) try to connect to the namenode, this is denied with:

2013-08-26 20:06:18,164 WARN org.apache.hadoop.hdfs.server.blockmanagement.DatanodeManager: Unresolved datanode registration from 10.20.30.114


it looks like the forced reverse DNS lookup in Datanodemanager.isNameResolved() fails to resolve the name for the IP, which is not unheared of in private network like 10.0.0.0/8.

a datanode on the namenode itself won't have this problem (since there is an exception in isNameResolved()).

the problem goes away after adding 10.20.30.114 to the namenode's /etc/hosts file.

This won't happen in Hadoop 2.0.2, but is present at least in 2.0.6 and 2.1.0.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira