This is the documentation for Cloudera Manager 4.8.2.
Documentation for other versions is available at Cloudera Documentation.

Using an External Database for Hue

By default, Cloudera Manager uses SQLite for Hue's database. If necessary, you can configure Cloudera Manager to use an external database such as MySQL or PostgreSQL as the database for Hue. The procedure described in this topic illustrates how to migrate the Hue database from the default SQLite installation to another database.

To configure Cloudera Manager to use an external database for Hue

  1. Using the Cloudera Manager Admin Console, click the service instance for the Hue database you are reconfiguring. The Hue service instance page in Cloudera Manager Admin Console appears.
  2. Click Actions and click Stop. Confirm you want to stop the service by clicking Stop. If the Hue service is already stopped, skip this step.
  3. Click Actions for the Hue service, and click Dump Database. Confirm you want to dump the database by clicking Dump Database.
  4. Open the database dump file (by default /tmp/hue_database_dump.json) and remove all JSON objects with 'useradmin.userprofile' in the 'model' field. (You can verify the location of the Database Dump File by searching for Database Dump File in the Hue Configuration settings.)

Continue with the following instructions for Configuring the Hue Server to Store Data in MySQL , Configuring the Hue Server to Store Data in PostgreSQL , or Configuring the Hue Server to Store Data in Oracle. When you complete the instructions, start the Hue server.

Configuring the Hue Server to Store Data in MySQL

To configure the Hue Server to store data in MySQL:

  1. Create a new database and grant privileges to a Hue user to manage this database. For example:
    mysql> create database hue;
    Query OK, 1 row affected (0.01 sec)
    mysql> grant all on hue.* to 'hue'@'localhost' identified by 'secretpassword';
    Query OK, 0 rows affected (0.00 sec)
  2. Using the Cloudera Manager Admin Console, click the service instance for the Hue database you are reconfiguring. The Hue service instance page in Cloudera Manager Admin Console appears.
  3. Click Configuration > View and Edit. In the Category pane, click the instance of Database under Service-Wide.
  4. Specify the settings for Hue's Database Type, Hue's Database Hostname, Hue's Database Port, Hue's Database Username, Hue's Database Password, and Hue's Database Name. For example, for a MySQL database on the local host, you might use the following values:
    Hue's Database Type = mysql
    Hue's Database Hostname = localhost
    Hue's Database Port = 3306
    Hue's Database Username = hue
    Hue's Database Password = secretpassword
    Hue's Database Name = hue
  5. The following steps are for restoring the Hue data to the new database. If you would like Hue to start from a fresh state, you can start your Hue service now.
  6. Click Actions and click Synchronize Database.
  7. Determine the foreign key ID.
    $ mysql -uhue -psecretpassword
    mysql > SHOW CREATE TABLE auth_permission;
  8. (InnoDB only) Drop the foreign key that you retrieved in the previous step.
    mysql > ALTER TABLE auth_permission DROP FOREIGN KEY content_type_id_refs_id_XXXXXX;
  9. Delete the rows in the django_content_type table.
    mysql > DELETE FROM hue.django_content_type;
  10. In Hue service instance page, click Actions, and click Load Database. Confirm you want to load the database by clicking Load Database.
  11. (InnoDB only) Add back the foreign key.
    mysql > ALTER TABLE auth_permission ADD FOREIGN KEY (`content_type_id`) REFERENCES `django_content_type` (`id`);

Configuring the Hue Server to Store Data in PostgreSQL

To configure the Hue Server to store data in PostgreSQL:

  1. Install required packages.

    To install on RHEL systems:

    $ sudo yum install postgresql-devel gcc python-devel

    To install on SLES systems:

    $ sudo zypper install postgresql-devel gcc python-devel

    To install on Ubuntu or Debian systems:

    $ sudo apt-get install postgresql-devel gcc python-devel
  2. Install the Python module that provides the connector to PostgreSQL:
    • Parcel install
      $ sudo /opt/cloudera/parcels/CDH/lib/hue/build/env/bin/pip install setuptools
      $ sudo /opt/cloudera/parcels/CDH/lib/hue/build/env/bin/pip install psycopg2
    • Package install
      sudo -u hue /usr/share/hue/build/env/bin/pip install setuptools
      sudo -u hue /usr/share/hue/build/env/bin/pip install psycopg2
  3. Install the PostgreSQL server.

    To install PostgreSQL on a RHEL system:

    $ sudo yum install postgresql-server

    To install PostgreSQL on SLES systems:

    $ sudo zypper install postgresql-server

    To install PostgreSQL on Ubuntu or Debian systems:

    $ sudo apt-get install postgresql
  4. Initialize the data directories.
    $ service postgresql initdb
  5. Configure client authentication.
    1. Edit /var/lib/pgsql/data/pg_hba.conf.
    2. Set the authentication methods for local to trust and for host to password and add the following line at the end.
      host	hue	hue	0.0.0.0/0	md5
  6. Start the PostgreSQL server.
    $ su - postgres
    # /usr/bin/postgres -D /var/lib/pgsql/data > logfile 2>&1 &
  7. Configure PostgreSQL to listen on all network interfaces.
    1. Edit /var/lib/pgsql/data/postgresql.conf and set list_addresses.
      listen_addresses = ‘0.0.0.0’     # Listen on all addresses
  8. Create the hue database and grant privileges to a hue user to manage the database.
    # psql -U postgres
    postgres=# create database hue;
    postgres=# \c hue;
    You are now connected to database 'hue'.
    postgres=# create user hue with password 'secretpassword';
    postgres=# grant all privileges on database hue to hue;
    postgres=# \q
  9. Restart the PostgreSQL server.
    $ sudo service postgresql restart
  10. Verify connectivity.
    psql –h localhost –U hue –d hue 
    Password for user hue: secretpassword
  11. Configure the PostgreSQL server to start at boot. '

    On RHEL systems:

    $ sudo /sbin/chkconfig postgresql on
    $ sudo /sbin/chkconfig --list postgresql
    postgresql          0:off   1:off   2:on    3:on    4:on    5:on    6:off

    On SLES systems:

    $ sudo chkconfig --add postgresql

    On Ubuntu or Debian systems:

    $ sudo chkconfig postgresql on
  12. Using the Cloudera Manager Admin Console, click the service instance for the Hue database you are reconfiguring. The Hue service instance page in Cloudera Manager Admin Console appears.
  13. Click Configuration > View and Edit. In the Category pane, click Advanced under Service-Wide.
  14. Specify the settings for Hue Server Configuration Safety Valve:
    [desktop]
    [[database]]
    host=localhost
    port=5432
    engine=postgresql_psycopg2
    user=hue
    password=secretpassword
    name=hue
  15. Click Save Changes.
  16. The following steps are for restoring the Hue data to the new database. If you would like Hue to start from a fresh state, you can start your Hue service now.
  17. Click Actions and click Synchronize Database.
  18. Determine the foreign key ID.
    bash# su – postgres
    $ psql –h localhost –U hue –d hue
    postgres=# \d auth_permission;
  19. Drop the foreign key that you retrieved in the previous step.
    postgres=# ALTER TABLE auth_permission DROP CONSTRAINT content_type_id_refs_id_XXXXXX;
  20. Delete the rows in the django_content_type table.
    postgres=# TRUNCATE django_content_type CASCADE;
  21. In Hue service instance page, click Actions, and click Load Database. Confirm you want to load the database by clicking Load Database.
  22. Add back the foreign key you dropped.
    bash# su – postgres
    $ psql –h localhost –U hue –d hue 
    postgres=# ALTER TABLE auth_permission ADD CONSTRAINT content_type_id_refs_id_XXXXXX FOREIGN KEY (content_type_id) REFERENCES django_content_type(id) DEFERRABLE INITIALLY DEFERRED;

Configuring the Hue Server to Store Data in Oracle

  1. Ensure Python 2.6 or newer is installed on the server Hue is running on.
  2. Download the Oracle client libraries at Instant Client for Linux x86-64 Version 11.1.0.7.0, Basic and SDK (with headers) zip files to the same directory.
  3. Unzip the zip files.
  4. Set environment variables to reference the libraries.
    $ export ORACLE_HOME=<download directory> 
    $ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ORACLE_HOME 
  5. Create a symbolic link for the shared object:
    $ cd $ORACLE_HOME 
    $ ln -sf libclntsh.so.11.1 libclntsh.so
  6. Install the Python Oracle library.
    $ <HUE_HOME>/build/env/bin/pip install cx_Oracle
  7. Upgrade django south.
    $ <HUE_HOME>/build/env/bin/pip install south --upgrade
  8. Get a data dump by executing:
    $ <HUE_HOME>/build/env/bin/hue dumpdata > <some-temporary-file>.json --indent 2  
  9. Open the Hue configuration file in a text editor.
  10. Directly below the [[database]] section under the [desktop] line, add the following options (and modify accordingly for your Oracle setup):
    host=localhost
    port=1521
    engine=oracle
    user=hue
    password=<secretpassword>
    name=<SID of the Oracle database, for example, 'XE'>
  11. As the hue user, configure Hue to load the existing data and create the necessary database tables. You will need to run both the syncdb and migrate commands.
    $ sudo -u hue <HUE_HOME>/build/env/bin/hue syncdb --noinput
    $ sudo -u hue <HUE_HOME>/build/env/bin/hue migrate
  12. Generate statements to delete all data from Oracle tables:
    > SELECT 'DELETE FROM ' || '.' || table_name || ';' FROM user_tables;   
  13. Run the statements generated in the preceding step.
  14. Load the data.
    $ sudo -u hue <HUE_HOME>/build/env/bin/hue loaddata <some-temporary-file>.json