HCatalog Connection

The HCatalog Connection shared resource contains all the necessary parameters to connect to HCatalog. It can be used by the Hive, MapReduce, Pig, and WaitForJobCompletion activities.

General

In the General panel, you can specify the package that stores the HCatalog Connection shared resource and the shared resource name.

The following table lists the fields in the General panel of the HCatalog Connection shared resource:

Field Module Property? Description
Package No The name of the package where the shared resource is located.
Name No The name as the label for the shared resource in the process.
Description No A short description for the shared resource.

HCatalogConnection Configuration

In the HCatalogConnection Configuration panel, you can provide necessary information to connect the plug-in with HCatalog. You can also connect to a Kerberized WebHcat server. The HCatalog Connection shared resource also supports the Knox Gateway security system provided by HortonWorks.

The following table lists the fields in the HCatalogConnection Configuration panel of the HCatalog Connection shared resource:

Field Module Property? Description
Select Url Type No The URL type used to connect to HCatalog. There are two types of URL:
  • WebHcat
  • Gateway

The default URL type is WebHcat when a new connection is created.

Gateway Url Yes This field is displayed when the Gateway option is selected in the Select Url Type field. The Knox Gateway URL is used to connect to HCatalog. For example, enter Knox Gateway URL as https://localhost:8443/gateway/default, where default is topology name.
Note: In Gateway URL, based on different topologies, the topology name is appended at the end of the URL.
HCatalog Url Yes This field is displayed when the Namenode option is selected in the Select Url Type field. The WebHCat URL that is used to connect to HCatalog. The default value is http://localhost:50111.
User Name Yes The unique user name that is used to connect to HCatalog.
Password Yes This field is displayed when the Gateway option is selected in the Select Url Type field. The password that is used to connect to HCatalog.
SSL No Select the check box to enable the SSL configuration. By default, the SSL check box is unchecked.
Key File Yes Select the server certificate for HCatalog. This field is displayed only when the SSL check box is selected.
Key Password Yes The password for the server certificate. This field is displayed only when the SSL check box is selected.
Trust File Yes Select the client certificate for HCatalog. This field is displayed only when the SSL check box is selected.
Trust Password Yes The password for the client certificate. This field is displayed only when the SSL check box is selected.
HDFSConnection No The HDFS Connection shared resource that is used to create a connection between the plug-in and HDFS. Click to select an HDFS Connection shared resource.

If no matching HDFS Connection shared resources are found, click Create Shared Resource to create one. For more details, see Creating an HDFS Connection.

Enable Kerberos No If you want to connect to a Kerberized WebHCat server, you can select this check box.
Note: If your server uses the AES-256 encryption, you must install Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files on your machine. For more details, see Installing JCE Policy Files.
Kerberos Method No The Kerberos authentication method that is used to authorize access to WebHCat. Select an authentication method from the list:
  • Keytab: specify a keytab file to authorize access to WebHCat.
  • Cached: use the cached credentials to authorize access to WebHCat.
  • Password: enter the name of the Kerberos principal and a password for the Kerberos principal.

This field is displayed only when you select the Enable Kerberos check box.

Kerberos Principal Yes The Kerberos principal name that is used to connect to WebHCat.

This field is displayed only when you select the Enable Kerberos check box.

Kerberos Password Yes The password for the Kerberos principal.

This field is displayed only when you select the Password from the Kerberos Method list.

Kerberos Keytab Yes The keytab that is used to connect to WebHCat.

This field is displayed only when you select Keytab from the Kerberos Method list.

Login Module File Yes The login module file is used to authorize access to WebHCat. Each LoginModule-specific item specifies a LoginModule, a flag value, and options to be passed to the LoginModule.

The login module file for Hadoop client is of the following format: 

HadoopClient 
{
  com.sun.security.auth.module.Krb5LoginModule required
	 useKeyTab=true
	 storeKey=false
	 debug=true
	 keyTab="<keytab file path>"
  principal="<Principal>";
};

For AIX platform, the login module file for Hadoop client is of the following format: 

HadoopClient 
{ 
  com.ibm.security.auth.module.Krb5LoginModule
  required principal="<Principal>" 
  useKeytab="<keytab file  path>" 
  credsType="both"; 
};

Test Connection

You can click Test Connection to test whether the specified configuration fields result in a valid connection.