Adjusting Oracle Settings to Accommodate Larger Clusters

Reserving Ports for HiveServer 2

HiveServer2 uses port 10000 by default, but Oracle database changes the local port range. This can cause HiveServer2 to fail to start.

Manually reserve the default port for HiveServer2. For example, the following command reserves port 10000 and inserts a comment indicating the reason:

echo << EOF > /etc/sysctl.cnf
# HS2 uses port 10000
net.ipv4.ip_local_reserved_ports = 10000
EOF

sysctl -q -w net.ipv4.ip_local_reserved_ports=10000

Modifying the Maximum Number of Oracle Connections

Work with your Oracle database administrator to ensure appropriate values are applied for your Oracle database settings. You must determine the number of connections, transactions, and sessions to be allowed.

Allow 100 maximum connections for each service that requires a database and then add 50 extra connections. For example, for two services, set the maximum connections to 250. If you have five services that require a database on one host (the databases for Cloudera Manager Server, Activity Monitor, Reports Manager, Cloudera Navigator, and Hive metastore), set the maximum connections to 550.

From the maximum number of connections, you can determine the number of anticipated sessions using the following formula:

sessions = (1.1 * maximum_connections) + 5

For example, if a host has a database for two services, anticipate 250 maximum connections. If you anticipate a maximum of 250 connections, plan for 280 sessions.

Once you know the number of sessions, you can determine the number of anticipated transactions using the following formula:

transactions = 1.1 * sessions

Continuing with the previous example, if you anticipate 280 sessions, you can plan for 308 transactions.

Work with your Oracle database administrator to apply these derived values to your system.

Using the sample values above, Oracle attributes would be set as follows:

alter system set processes=250;
alter system set transactions=308;
alter system set sessions=280;

Ensuring Your Oracle Database Supports UTF8

The database you use must support UTF8 character set encoding. You can implement UTF8 character set encoding in Oracle databases by using the dbca utility. In this case, you can use the characterSet AL32UTF8 option to specify proper encoding. Consult your DBA to ensure UTF8 encoding is properly configured.

• Cloudera Manager Server
• Cloudera Management Service roles:
  • Activity Monitor (if using the MapReduce service)
  • Reports Manager
  • Cloudera Navigator Audit Server
  • Cloudera Navigator Metadata Server
• Hive Metastore
• Sentry Server

You can create the Oracle database, schema and users on the host where the Cloudera Manager Server will run, or on any other hosts in the cluster. For performance reasons, you should install each database on the host on which the service runs, as determined by the roles you assign during installation or upgrade. In larger deployments or in cases where database administrators are managing the databases the services use, you can separate databases from services, but use caution.

The database must be configured to support UTF-8 character set encoding.

Record the values you enter for database names, usernames, and passwords. The Cloudera Manager installation wizard requires this information to correctly connect to these databases.

1. Log into the Oracle client:

   sqlplus system@localhost

   Enter password: ******

2. Create a user and schema for each service you are using from the below table:

   create user <user> identified by <password> default tablespace <tablespace>;
   grant CREATE SESSION to <user>;
   grant CREATE TABLE to <user>;
   grant CREATE SEQUENCE to <user>;
   grant EXECUTE on sys.dbms_lob to <user>;

   You can use any value you want for <schema>, <user>, and <password>. The following examples are the default names provided in the Cloudera Manager configuration settings, but you are not required to use them:

   Table 1. Databases for Cloudera Software

   Service	Database	User
   Cloudera Manager Server	scm	scm
   Activity Monitor	amon	amon
   Reports Manager	rman	rman
   Hue	hue	hue
   Hive Metastore Server	metastore	hive
   Sentry Server	sentry	sentry
   Cloudera Navigator Audit Server	nav	nav
   Cloudera Navigator Metadata Server	navms	navms
   Oozie	oozie	oozie

3. Grant a quota on the tablespace (the default tablespace is SYSTEM) where tables will be created:

   ALTER USER <user> quota 100m on <tablespace>;

   or for unlimited space:

   ALTER USER username quota unlimited on <tablespace>;

4. Set the following additional privileges for Oozie:

   grant alter index to oozie;
   grant alter table to oozie;
   grant create index to oozie;
   grant create sequence to oozie;
   grant create session to oozie;
   grant create table to oozie;
   grant drop sequence to oozie;
   grant select dictionary to oozie;
   grant drop table to oozie;
   alter user oozie quota unlimited on <tablespace>;

     Important:

   For security reasons, do not grant select any table privileges to the Oozie user.

5. Set the following additional privileges for the Cloudera Navigator Audit Server database:

   GRANT EXECUTE ON sys.dbms_crypto TO nav;
   GRANT CREATE VIEW TO nav;

   where <nav> is the Navigator Audit Server user you specified above when you created the database.

For further information about Oracle privileges, see Authorization: Privileges, Roles, Profiles, and Resource Limitations.