4. DistCp and Security Settings

Security settings dictate whether DistCp should be run on the source cluster or the destination cluster. The general rule-of-thumb is that if one cluster is secure and the other is not secure, DistCp should be run from the secure cluster -- otherwise there may be security- related issues.

When copying data from a secure cluster to an non-secure cluster, the following configuration setting is required for the DistCp client:

<property>
 <name>ipc.client.fallback-to-simple-auth-allowed</name>
 <value>true</value>
</property>

When copying data from a secure cluster to a secure cluster, the following configuration setting is required in the core-site.xml file:

<property>
    <name>hadoop.security.auth_to_local</name>
    <value></value>
    <description>Maps kerberos principals to local user names</description>
</property>