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Haohui Mai commented on HDFS-6776: ---------------------------------- I'm unsure that fixing on the filesystem itself is the right approach to take. Based on the above comments (and please correct me if I'm wrong), I'm assuming that distcp is pulling data from a secure cluster to an insecure cluster. # What happens if the {{WebHdfsFileSystem}} intends to connect to a secure cluster but the attacker has somehow disabled the security of the cluster or successfully launch a MITM attack which keep returning {{NullToken}}? Instead of ignoring the failures, I think that {{WebHdfsFileSystem}} should fail explicitly because that the system is compromised. This is important as copying from a secure cluster to an insecure cluster can unintentionally breach the confidentiality. On the implementation: # It looks like that {{WebHdfsFileSystem}} will issue a {{GET_DELEGATION_TOKEN}} request for each request since in catching {{NullToken}} nullifies {{delegationToken}}, which significantly affects the performance. I have encountered this issue in production. What I have done is to put the fix on the server side instead of the client side. I asked the NN of the insecure cluster to issue a dummy token, which works across all filesystems. That way at the very least the user has to be informed instead of allowing the data silently flowing from secure to insecure clusters. > distcp from insecure cluster (source) to secure cluster (destination) doesn't > work > ---------------------------------------------------------------------------------- > > Key: HDFS-6776 > URL: https://issues.apache.org/jira/browse/HDFS-6776 > Project: Hadoop HDFS > Issue Type: Bug > Affects Versions: 2.3.0, 2.5.0 > Reporter: Yongjun Zhang > Assignee: Yongjun Zhang > Attachments: HDFS-6776.001.patch, HDFS-6776.002.patch, > HDFS-6776.003.patch, HDFS-6776.004.patch, HDFS-6776.004.patch, > HDFS-6776.005.patch, HDFS-6776.006.NullToken.patch, > HDFS-6776.006.NullToken.patch, HDFS-6776.007.patch > > > Issuing distcp command at the secure cluster side, trying to copy stuff from > insecure cluster to secure cluster, and see the following problem: > {code} > hadoopuser@yjc5u-1 ~]$ hadoop distcp webhdfs://<insure-cluster>:<port>/tmp > hdfs://<sure-cluster>:8020/tmp/tmptgt > 14/07/30 20:06:19 INFO tools.DistCp: Input Options: > DistCpOptions{atomicCommit=false, syncFolder=false, deleteMissing=false, > ignoreFailures=false, maxMaps=20, sslConfigurationFile='null', > copyStrategy='uniformsize', sourceFileListing=null, > sourcePaths=[webhdfs://<insecure-cluster>:<port>/tmp], > targetPath=hdfs://<secure-cluster>:8020/tmp/tmptgt, targetPathExists=true} > 14/07/30 20:06:19 INFO client.RMProxy: Connecting to ResourceManager at > <secure-clister>:8032 > 14/07/30 20:06:20 WARN ssl.FileBasedKeyStoresFactory: The property > 'ssl.client.truststore.location' has not been set, no TrustStore will be > loaded > 14/07/30 20:06:20 WARN security.UserGroupInformation: > PriviledgedActionException as:hadoopu...@xyz.com (auth:KERBEROS) > cause:java.io.IOException: Failed to get the token for hadoopuser, > user=hadoopuser > 14/07/30 20:06:20 WARN security.UserGroupInformation: > PriviledgedActionException as:hadoopu...@xyz.com (auth:KERBEROS) > cause:java.io.IOException: Failed to get the token for hadoopuser, > user=hadoopuser > 14/07/30 20:06:20 ERROR tools.DistCp: Exception encountered > java.io.IOException: Failed to get the token for hadoopuser, user=hadoopuser > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) > at > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) > at > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) > at java.lang.reflect.Constructor.newInstance(Constructor.java:526) > at > org.apache.hadoop.ipc.RemoteException.instantiateException(RemoteException.java:106) > at > org.apache.hadoop.ipc.RemoteException.unwrapRemoteException(RemoteException.java:95) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.toIOException(WebHdfsFileSystem.java:365) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.access$600(WebHdfsFileSystem.java:84) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.shouldRetry(WebHdfsFileSystem.java:618) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.runWithRetry(WebHdfsFileSystem.java:584) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.access$100(WebHdfsFileSystem.java:438) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner$1.run(WebHdfsFileSystem.java:466) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:415) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1554) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.run(WebHdfsFileSystem.java:462) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getDelegationToken(WebHdfsFileSystem.java:1132) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getDelegationToken(WebHdfsFileSystem.java:218) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getAuthParameters(WebHdfsFileSystem.java:403) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.toUrl(WebHdfsFileSystem.java:424) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractFsPathRunner.getUrl(WebHdfsFileSystem.java:640) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.runWithRetry(WebHdfsFileSystem.java:565) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.access$100(WebHdfsFileSystem.java:438) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner$1.run(WebHdfsFileSystem.java:466) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:415) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1554) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.run(WebHdfsFileSystem.java:462) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getHdfsFileStatus(WebHdfsFileSystem.java:781) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.getFileStatus(WebHdfsFileSystem.java:796) > at org.apache.hadoop.fs.Globber.getFileStatus(Globber.java:57) > at org.apache.hadoop.fs.Globber.glob(Globber.java:248) > at org.apache.hadoop.fs.FileSystem.globStatus(FileSystem.java:1623) > at > org.apache.hadoop.tools.GlobbedCopyListing.doBuildListing(GlobbedCopyListing.java:77) > at org.apache.hadoop.tools.CopyListing.buildListing(CopyListing.java:81) > at > org.apache.hadoop.tools.DistCp.createInputFileListing(DistCp.java:342) > at org.apache.hadoop.tools.DistCp.execute(DistCp.java:154) > at org.apache.hadoop.tools.DistCp.run(DistCp.java:121) > at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70) > at org.apache.hadoop.tools.DistCp.main(DistCp.java:390) > Caused by: org.apache.hadoop.ipc.RemoteException(java.io.IOException): Failed > to get the token for hadoopuser, user=hadoopuser > at > org.apache.hadoop.hdfs.web.JsonUtil.toRemoteException(JsonUtil.java:159) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.validateResponse(WebHdfsFileSystem.java:334) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem.access$200(WebHdfsFileSystem.java:84) > at > org.apache.hadoop.hdfs.web.WebHdfsFileSystem$AbstractRunner.runWithRetry(WebHdfsFileSystem.java:570) > ... 30 more > [hadoopuser@yjc5u-1 ~]$ > {code} -- This message was sent by Atlassian JIRA (v6.2#6252)