PolyBase Settings Folder in SQL Server 2016

PolyBase in SQL Server 2016 currently has multiple configuration files.
Kerberos:  several have kerberos sections, see https://msdn.microsoft.com/en-us/library/mt712797.aspx, for more details under the kerberos section.


Located in the folder:
C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Binn\Polybase\

.config:

1. Dms.config
2. DWEngineService.exe.config

.conf

1. jaas.conf

.xml

1. FailoverDiagnosticsConfig.xml
2. EngineDiagnosticsConfig.xml
3. EngineDiagnosticsCloudMdsConfig.xml
4. DmsDiagnosticsConfig.xml
5. DmsDiagnosticsCloudMdsConfig.xml
6. DmsCommonDiagnosticsConfig.xml
7. CommonDiagnosticsConfig.xml

Located in the folder:     C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\ MSSQL\Binn\Polybase\hadoop\conf

1. core-site.xml
2. yarn-site.xml
3. mapred-site.xml
4. hive-site.xml
5. hdfs-site.xml

Earlier CTP releases:

we had these additional files.  It is unclear

1. Backup.config
2. Copy.config
3. CostModel.config
4. Dsql.config
5. Hadoop.config
6. Monitoring.config
7. Server.config

For CTP 2.2, most, perhaps all of these may never need to be changed.
These are located in the folder:
C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Binn\Polybase\Settings\.

HadoopUserName

Located in Hadoop.config file, the setting HadoopUserName has a default of pdw_user.

      <setting name="HadoopUserName" serializeAs="String">
           <value>pdw_user</value>
     </setting>


We did not have to change this value, but we were using the fairly open Hortonworks Sandbox with the user Hue. However, this value does seem to be a setting used by HDInsight. Until additional documentation is released, if you are have having connection issues, this might be a setting you want to consider updating. Thanks to Hilmar Buchta for pointing out this hidden user name setting.