Error when querying dataset


When I’m trying to query a dataset, I have the following error : User: dremio is not allowed to impersonate arnault.

I didn’t see anything in the conf file where one can find impersonation settings.

Thank you in advance.


Hi Arnault,

What data source are you trying to query?

Did you happen to see this page in the documentation on Impersonation?

Ae you using dataset on HDFS? Did you enable impersonation while creating HDFS based source?
If both are “yes” - you would need to change your core-site.xml to allow user “dremio” to impersonate other users:
Just use user “dremio” instead of Oozie. And don’t forget to restart Hadoop services for this setting to take effect.

Usually this error is thrown by the HDFS or Hive metastore. These systems should contain proxy settings to allow user “dremio” to impersonate other users.

See for more details. It requires restart of HDFS or Hive metastore.

If this doesn’t resolve could you please upload the profile of the job where this error happened?

To avoid a costly HDFS restart, you can use " hdfs dfsadmin -refreshSuperUserGroupsConfiguration" .
This will update the super user configuration for the HDFS system immediately.

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I am trying to connect to Hive. getting the same error. Any suggestion for this. Even logs show the same error saying : " Caused by: org.apache.hadoop.ipc.RemoteException: User: dremio is not allowed to impersonate demo_user


That error means that the user running the Dremio process cannot impersonate the user trying to access data. You can disable this by editing the Hive settings in the Dremio UI and setting hive.server2.enable.doAs to false:

You can learn more about impersonation at

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