As explained in the properties table, when you select the Custom option from the Distribution drop-down list, you are connecting to a Hadoop distribution different from any of the Hadoop distributions provided on that Distribution list in the Studio.
After selecting this Custom option, click the button to display the [Import custom definition] dialog box and proceed as follows:
Depending on your situation, select Import from existing version or Import from zip to configure the custom Hadoop distribution to be connected to.
If you have the zip file of the custom Hadoop distribution you need to connect to, select Import from zip. Talend community provides this kind of zip files that you can download from http://www.talendforge.org/exchange/index.php.
Otherwise, select Import from existing version to import an officially supported Hadoop distribution as base so as to customize it by following the wizard.
Note that the check boxes in the wizard allow you to select the Hadoop element(s) you need to import. All the check boxes are not always displayed in your wizard depending on the context in which you are creating the connection. For example, if you are creating this connection for a Hive component, then only the Hive check box appears.
Whether you have selected Import from existing version or Import from zip, verify that each check box next to the Hadoop element you need to import has been selected..
Click OK and then in the pop-up warning, click Yes to accept overwriting any custom setup of jar files previously implemented.
Once done, the [Custom Hadoop version definition] dialog box becomes active.
This dialog box lists the Hadoop elements and their jar files you are importing.
If you have selected Import from zip, click OK to validate the imported configuration.
If you have selected Import from existing version as base, you should still need to add more jar files to customize that version. Then from the tab of the Hadoop element you need to customize, for example, the HDFS/HCatalog/Oozie tab, click the [+] button to open the [Select libraries] dialog box.
Select the External libraries option to open its view.
Browse to and select any jar file you need to import.
Click OK to validate the changes and to close the [Select libraries] dialog box.
Once done, the selected jar file appears on the list in the tab of the Hadoop element being configured.
Note that if you need to share the custom Hadoop setup with another Studio, you can export this custom connection from the [Custom Hadoop version definition] window using the button.
In the [Custom Hadoop version definition] dialog box, click OK to validate the customized configuration. This brings you back to the Distribution list in the Basic settings view of the component.
Now that the configuration of the custom Hadoop version has been set up and you are back to the Distribution list, you are able to continue to enter other parameters required by the connection.
If the custom Hadoop version you need to connect to contains YARN and you want to use it, select the Use YARN check box next to the Distribution list.