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copy stuff with distcp from insecure cluster to secure cluster. Please help to me.

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Unable to copy data from non kerberos cluster to kerberized cluster, getting below error

18/04/20 02:20:15 ERROR tools.DistCp: Invalid arguments: Authentication required at org.apache.hadoop.hdfs.web.WebHdfsFileSystem.validateResponse( at org.apache.hadoop.hdfs.web.WebHdfsFileSystem.access$200( at org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.runWithRetry( at org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.access$100( at org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner$ at Method) at at at org.apache.hadoop.hdfs.web.WebHdfsFileSystem$ at org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getHdfsFileStatus( at org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getFileStatus( at org.apache.hadoop.fs.FileSystem.exists( at at at at Invalid arguments: Authentication required usage: distcp OPTIONS [source_path...] <target_path>


Re: copy stuff with distcp from insecure cluster to secure cluster. Please help to me.


@venkata ramireddy

You can use DistCp and WebHDFS to copy data between a secure cluster and an insecure cluster by doing the following:

Set ipc.client.fallback-to-simple-auth-allowed to true in core-site.xml on the secure cluster side:


Use commands such as the following from the secure cluster side only:

distcp webhdfs://insecureCluster webhdfs://secureCluster 
distcp webhdfs://secureCluster webhdfs://insecureCluster

I have found that using webhdfs instead of hdfs for the nonsecure host gets around this error by setting ipc.client.fallback-to-simple-auth-allowed=true on the console while running DISTCP

"hadoop distcp -D ipc.client.fallback-to-simple-auth-allowed=true webhdfs://nn1:8020/foo/bar hdfs://nn2:8020/bar/foo"

Hope that helps