Performing an Oracle database health check? We have a little list
Guidelines for the diligent DBA
Workshop Everyone needs a checkup from time to time, and your Oracle database is no exception. A periodic medical can keep it running smoothly, and avoid more serious conditions from developing later.
Here is a guide to help ensure optimal performance, with a series of checkpoints that can form the basis for a regular database review.
You can use the Health Monitor available in release 11g to assess several aspects of your database's health. These include various data integrity checks for file structure, REDO logs and undo segments.
You can also use Toad for Oracle, which is one of the most popular third party administrator tools for the Oracle database. Toad users can launch database health checks either from the database browser, or from the diagnose menu.
One of the areas that Toad for Oracle focuses on is security. DBAs can find the vulnerability assessment under its own category. It includes a variety of vulnerability checks, alongside an 'explainer' column, providing a description of each check as a friendly reminder to the DBA.
The assessment checks in Toad are many and varied, but they include listing listing hidden users and nested roles, and listing GRANTs on SYS tables granted directly to users.
DBAs can check many aspects of their Oracle database's health, and any health check should include a thorough security audit to ensure that there is no light leakage. A review should include the following:
- Patch management procedures.
- Backup recovery (test it).
- User password management and access controls.
- User roles and responsibilities.
- Configuration parameters.
- How your audit trail is configured.
- Privileges (how are system and object privileges assigned? Who has them?)
- Access to Oracle packages and privileges, including operating system access.
- Which PL/SQL and Java is used, and how.
Monitor and optimize your use of database space. There are two ways to do this: proactive tablespace management (PTM), and shrinking segments. Under PTM, Oracle warns database administrators when available space is running low. It has two thresholds when alerts are triggered: critical, and warning.
You can conduct this health check incrementally as space frees up in the database server, which helps you make space available to users when needed. Check the critical and warning thresholds of the table spaces to know how much of your table space is being used. By default, the settings are 97% critical and 85% warning.
Segment shrinkage makes unused space available to other segments in the tablespace. You can shrink a segment using the Enterprise Manager.