This article can also be found in the Premium Editorial Download "Storage magazine: Storage salary survey: Are you being paid enough?."
Download it now to read this article plus other related content.
Information lifecycle management (ILM) is not a product or technology; rather it is a process or approach to managing information, data and storage in a more effective manner. There are vendors who leverage and link ILM as a buzzword to their products. Consequently there are those who believe that ILM is software while others believe that ILM is hardware, such as tiered storage, virtual tape, or object based storage.
In the context of tiered storage, some vendors have done an effective job of linking ILM to mean different categories of data storage -- including on-line, near-line and off-line. Other vendors have done an effective marketing job of associating ILM to archiving or data storage resource management/monitoring (SRM) software, among other things.
Without going off on a tangent or philosophical discussion as to what is and what is not ILM (we can do that some other time), lets take look at what your data storage options are for an Oracle environment. Since Oracle databases can be deployed to support different applications and workloads, let's keep this generic. This is by no means a comprehensive list.
|Storage Category (Tier)||Applications||Characteristics||Examples|
|On-line Primary Tier-1||Primary tables, indices, journals and transaction logs that are update and I/O intensive or that need high availability.||High performance, reliability, advanced features and large capacity. High performance disk drives such as Fibre Channel, SAS or SCSI are used. Compare on an effective and protected dollar per I/O per GB instead of simply on a dollar per GB basis.||EMC Symmetrix and CLARiiON, HP XP and EVA, HDS Tagmastore, IBM DS8000 & DS4000, NetApp, SGI, Sun/STK SVA and FLX200/300, 3PAR, Xiotech among others.|
|Near-line Secondary Tier-2||Less frequently used data with little to no I/O or updates, I/O may be more reads than writes. storage centric data including historical data, videos, images, audio and other large objects, import and export areas, scratch space and space for backups.||Ok to good performance and reliability with ultra large storage capacity for less frequently used or static data also known as fixed content. Lower cost compared to on-line storage with better performance and accessibility than off-line storage. This may also include disk based libraries that emulate and function as tape libraries for disk to disk based backup and archives.||SATA and FATA configured storage from EMC, HP, HDS, IBM, NetApp, Nexsan, Sun/STK, Xiotech and others. Fixed content and object based storage also known as CAS such as EMC Centera, HP RISS, IBM DR550 and others including Nexsan, STK and Bycast.|
|Off-line Tertiary Tier-3||Backup for DR and BC, archive, long term retention for compliance and other data preservation needs.||Lower performance compared too many disk solutions however with ultra large storage capacity and relatively low cost of data storage. May be disk based, tape based, optical or a combination supporting block, file or object based access.||Tape drives and libraries along with virtual tape libraries and disk libraries from EMC, HP, IBM, Quantum, Sun/STK and others. Object based storage and optical storage.|
Which type of data storage is most applicable depends upon your environment, how your applications are configured to support different workloads, and service requirements. Looking beyond simple dollar per GB is an important step to aligning the right type of technology to meet your application needs. Look at the effective cost and ennoblement benefit while understanding your business and application needs.
- For more information of information lifecycle management (ILM) data storage, read a chapter excerpt from Data protection and information lifecycle management.
This was first published in January 2006