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Configure Database for DBFS on Exadata Database Machine

Overview
When you configure DBFS on Exadata, it recommended configuring a separate database to be used for DBFS. In this article we will demonstrate how to create a Database to store DBSF (Database File System) on Exadata Database Machine. Using DBCA (Database Configuration Assistance) Utility is the recommended method for creating a Database to store DBFS.

Environment
Exadata X4-2 Quarter Rack


Steps to Create a Database Create a Database


  • Login to the Exadata Compute node 1, export DISPLAY variable and Invoke DBCA utility



  • Choose the first option “Real Application Clusters (RAC) database.” Click Next



  • Choose the option “Create a Database”. Click Next



  • Choose the option “General Purpose or Transaction Processing template”. Click Next



  • Choose the option “Admin-Managed”, select all nodes and Enter Name your database. Here we are specifying the Database name as “fsdb”. Click Next



  • Uncheck “configure Enterprise Manager” as we will be managing this database using OEM. Enable automatic maintenance tasks as per site requirements. Click Next



  • Select “Use the Same Administrative Password for All Account” and enter a password. Click Next



  • Ignore the warning and click Yes to continue



  • Choose Automatic Storage Management and Oracle-Managed Files. Select the desired Disk Group FLASH_DATA01. This DG has adequate space for DBFS database. Click Next



  • Uncheck Flash Recovery Area and Uncheck Enable Archiving. For DBFS database Archive log mode is not necessary. Click Next



  • Click Next



  • In the Memory Tab, choose Custom and then Automatic Shared Memory Management. Enter 1536 and choose M Bytes for units in the SGA box and enter 6656 and choose M Bytes for units in the PGA Size box. 



  • In the Character Sets tab choose AL32UTF8 as the Database Character Set and AL16UTF16 as National Character set. Click Next



  • Open the All Initialization Parameters dialogue. Select “Show Advanced Parameters”. Scroll down to parallel_max_servers and enter “2” under the Value column



  • If diskgroup DBFS_DG’s compatible.rdbms attribute is set to 11.2.0.4.0 then in DBCA set compatible=11.2.0.4.0 in All Initialization Parameters screen.

Not setting compatible.rdbms properly can result in ORA-15204 error while creating the database. Click Close


  • Click Finish

Wait for the DBCA to complete creating the database.


Check the database status using srvctl command.

oraclouddbadm01-dbm011 {/home/oracle}:srvctl status database -d fsdb

Instance fsdb1 is running on node oraclouddbadm01

Instance fsdb2 is running on node oraclouddbadm02


Important Notes:

1.      See MOS note: 1468931.1 for issues related to running DBCA.
2.      The default Redo log size chooses by DBCA template is sufficient.
3.      You can create tablespace for DBFS as either SMALLFILE or BIGFILE.
4.      Include the following options when creating a tablespace for DBFS:
NOLOGGING ONLINE PERMANENT EXTENT MANAGEMENT LOCAL AUTOALLOCATE  SEGMENT SPACE MANAGEMENT AUTO
Example:

SQL> create bigfile tablespace dbfsts datafile ‘+FLASH_DATA01’ size 100g autoextend on next 8g maxsize 300g NOLOGGING EXTENT MANAGEMENT LOCAL AUTOALLOCATE  SEGMENT SPACE MANAGEMENT AUTO ;