Oracle 19c ASM: Oracle simplified

Storage Management Built for Oracle Database ⚙️

Oracle Automatic Storage Management takes the messy parts of database storage — volume managers, raw devices, hand-tuned file systems — and folds them into a single layer designed specifically for Oracle Database files. Oracle 19c ASM: Oracle simplified works through how that layer is structured and how it is administered in a 19c environment.

The guide opens with the Oracle ASM instance itself: its System Global Area, background processes, and the way it mounts disk groups for database instances to use. From there it moves steadily outward into the objects and operations that DBAs work with every day.

Disk Groups, Redundancy and Striping

A disk group is the fundamental unit Oracle ASM manages, and the book gives it the attention it deserves. It explains how disks, files and allocation units fit together, how Oracle ASM spreads data proportionally to keep every disk at the same capacity and I/O load, and how mirroring protects that data across failure groups.

Normal, high and external redundancy are each covered, along with the practical consequence that a disk group’s redundancy level cannot be altered after creation. Extent sizing and striping are also unpacked — including the distinction between coarse-grained striping for load balancing and fine-grained striping for lower latency — so readers can reason about performance rather than just repeat configuration defaults.

Files, Templates and Everyday Administration

Beyond the storage model, the guide turns to the tasks that keep an ASM environment running: discovering disks, managing capacity, maintaining disk groups, working with flex disk groups, and setting up Oracle ASM files, directories and templates. Compatibility attributes, file access control and the views used to inspect Oracle ASM information are all part of the picture.

Initialization parameters, instance verification, audit trail administration and the process for creating database files through SQL*Plus round out the administration material.

ACFS, ADVM and the Wider Toolset 💡

Oracle ASM does not stop at database files. The book introduces Oracle Automatic Storage Management Cluster File System (ACFS) and Oracle ASM Dynamic Volume Manager (ADVM), explaining how they extend ASM functionality to broader storage needs. ACFS administration, the views that report ACFS information, and command-line management are all addressed.

Administration is also presented through the tools DBAs actually reach for: ASMCA, ASMCMD, SQL*Plus and Oracle Enterprise Manager, with a section on performing Oracle ASM data migration using RMAN.

Who This Guide Suits

This is a working reference for database administrators, infrastructure engineers and Oracle professionals who need to understand how ASM storage behaves in Oracle 19c — whether they are building a new configuration, troubleshooting an existing one, or preparing for the storage questions that come up in Oracle certification study.

Structured for both sequential reading and targeted lookup, it keeps the explanations close to the concepts that matter: how Oracle ASM instances operate, how disk groups are organised, and which tools and commands do the work.