Specifying the Hue Server HTTP Address

These configuration properties are under the [desktop] section in the Hue configuration file.

# Webserver listens on this address and port 
http_host=0.0.0.0 
http_port=8888

Specifying the Secret Key

For security, you should specify the secret key that is used for secure hashing in the session store:

1. Open the Hue configuration file.
2. In the [desktop] section, set the secret_key property to a long series of random characters (30 to 60 characters is recommended). For example,

   secret_key=qpbdxoewsqlkhztybvfidtvwekftusgdlofbcfghaswuicmqp

     Note: If you do not specify a secret key, your session cookies will not be secure. Hue will run but it will also display error messages telling you to set the secret key.

Authentication

In a non-secure deployment, the first user who logs in to Hue can choose any username and password and automatically becomes an administrator. This user can create other user and administrator accounts. Hue users should correspond to the Linux users who use Hue; make sure you use the same name as the Linux username.

By default, user information is stored in the Hue database. However, the authentication system is pluggable. You can authenticate Hue with LDAP (Active Directory or OpenLDAP), or you can import users and groups from an LDAP directory.

Configuring the Hue Server for TLS/SSL

You can optionally configure Hue to serve over HTTPS. As of CDH 5, pyOpenSSL is now part of the Hue build and does not need to be installed manually. To configure TLS/SSL, perform the following steps from the root of your Hue installation path:

1. Configure Hue to use your private key by adding the following options to the Hue configuration file:

   ssl_certificate=/path/to/certificate
   ssl_private_key=/path/to/key

     Note: Hue can only support a private key without a passphrase.
2. On a production system, you should have an appropriate key signed by a well-known Certificate Authority. If you're just testing, you can create a self-signed key using the openssl command that may be installed on your system:

   # Create a key 
   $ openssl genrsa 1024 > host.key 
   # Create a self-signed certificate 
   $ openssl req -new -x509 -nodes -sha1 -key host.key > host.cert

     Note: Uploading files using the Hue File Browser over HTTPS requires using a proper TLS/SSL Certificate. Self-signed certificates do not work.

Authentication Backend Options for Hue

The table below gives a list of authentication backends Hue can be configured with including the recent SAML backend that enables single sign-on authentication. The backend configuration property is available in the [[auth]] section under [desktop].

  Note: All backends that delegate authentication to a third-party authentication server eventually import users into the Hue database. While the metadata is stored in the database, user authentication will still take place outside Hue.

HDFS Cluster Configuration

Hue currently supports only one HDFS cluster, which you define under the [[hdfs_clusters]] sub-section. The following properties are supported:

YARN (MRv2) and MapReduce (MRv1) Cluster Configuration

Job Browser can display both MRv1 and MRv2 jobs, but must be configured to display one type at a time by specifying either [[yarn_clusters]] or [[mapred_clusters]] sections in the Hue configuration file.

The following YARN cluster properties are defined under the under the [[yarn_clusters]] sub-section:

The following MapReduce cluster properties are defined under the [[mapred_clusters]] sub-section:

[[[default]]]	The section containing the default settings.
jobtracker_host	The fully qualified domain name of the host running the JobTracker.
jobtracker_port	The port for the JobTracker IPC service.
submit_to	If your Oozie is configured with to use a 0.20 MapReduce service, then set this to true. Indicate that Hue should submit jobs to this MapReduce cluster.

  Note: High Availability (MRv1):

Add High Availability (HA) support for your MRv1 cluster by specifying a failover JobTracker. You can do this by configuring the following property under the [[[ha]]] sub-section for MRv1.

# Enter the host on which you are running the failover JobTracker      
# jobtracker_host=<localhost-ha>

High Availability (YARN):

Add the following [[[ha]]] section under the [hadoop] > [[yarn_clusters]] sub-section in hue.ini with configuration properties for a second ResourceManager. As long as you have the logical_name property specified as below, jobs submitted to Oozie will work. The Job Browser, however, will not work with HA in this case.

[[[ha]]]
resourcemanager_host=<second_resource_manager_host_FQDN>
resourcemanager_api_url=http://<second_resource_manager_host_URL>
proxy_api_url=<second_resource_manager_proxy_URL>
history_server_api_url=<history_server_API_URL>
resourcemanager_port=<port_for_RM_IPC>
security_enabled=false
submit_to=true
logical_name=XXXX

Setting up REST Service for ZooKeeper

ZooKeeper Browser requires the ZooKeeper REST service to be running. Follow the instructions below to set this up.

Step 1: Git and build the ZooKeeper repository

git clone https://github.com/apache/zookeeper
cd zookeeper
ant
Buildfile: /home/hue/Development/zookeeper/build.xml

init:
[mkdir] Created dir: /home/hue/Development/zookeeper/build/classes
[mkdir] Created dir: /home/hue/Development/zookeeper/build/lib
[mkdir] Created dir: /home/hue/Development/zookeeper/build/package/lib
[mkdir] Created dir: /home/hue/Development/zookeeper/build/test/lib
…

Step 2: Start the REST service

cd src/contrib/rest
nohup ant run&

Step 3: Update ZooKeeper configuration properties (if required)

If ZooKeeper and the REST service are not on the same machine as Hue, update the Hue configuration file and specify the correct hostnames and ports as shown in the sample configuration below:

[zookeeper]
        ...
        [[clusters]]
                ...
                [[[default]]]
          # Zookeeper ensemble. Comma separated list of Host/Port.
          # e.g. localhost:2181,localhost:2182,localhost:2183
          ## host_ports=localhost:2181

          # The URL of the REST contrib service
          ## rest_url=http://localhost:9998

You should now be able to successfully run the ZooKeeper Browser app.