Managing storage is one of the most complex and time-consuming tasks of a DBA. Data grows at an exponential pace due to the consolidation of databases, as well as the growth of a business over time. Business requirements demand the continuous availability of database storage systems, and the maintenance window for storage is shrinking from hours to minutes. Legal and compliance requirements add even more baggage because increasingly, organizations are required to retain data for extended periods of time. (We know some sites that store hundreds of terabytes of active data for seven years or more!)
Oracle Automatic Storage Management (Oracle ASM), Oracle ASM Cluster File System (Oracle ACFS), and Oracle ASM Dynamic Volume Manager (Oracle ADVM) are the key components of Oracle RAC storage management. Storage management has changed significantly over the past several years. You can now have remote ASM-based systems that use some form of a NFS (Network File System) for shared storage as well as appliances such as the Oracle Data Appliance, which has an NFS-based mechanism to expose ASM/ACFS to the virtual machines (VMs). In addition, some cloud-based storage solutions such as Amazon EC2/S3 and Microsoft Azure aren’t capable of hosting Oracle RAC–based systems yet, but work is in progress to make this possible in these types of environments. Oracle’s public cloud is also something you can use in case you can’t allocate on-premises storage.
Modern technologies help DBAs easily manage huge volumes of data without a considerable amount of administrative overhead. New tools are being developed that work closely with the RDBMS kernel to make data management and data consolidation easier. Automatic Storage Management (affectionately called Awesome Storage Management) is one of those revolutionary solutions from Oracle. After introducing Automatic Storage Management in Oracle Database 10g, Oracle has enhanced it over the following Oracle Database releases to provide a complete volume manager built into Oracle database software. The Oracle ASM file system is highly optimized to provide raw disk performance by avoiding various types of overhead associated with a conventional file system.