The Complex Relationship Between Content Management and Storage
Content management systems need robust storage management. These systems rely on complex databases that store metadata, usage statistics, user data, and the content itself with each type of data having different storage requirements.
Nevertheless, many of the Web-based content management systems don't offer storage management because bandwidth is plentiful and storage has become inexpensive. Also, some storage options, such as DVD jukeboxes and network attached storage devices, include some type of storage management software. You can also use most off-the-shelf storage management software with just about any application, not just content management. So why buy something you might have already?
Because content management vendors don't specialize in storage. In fact, to them, storage functions only as a utility enabling application vendors to concentrate on content. On the other hand, if your storage system doesn't carefully match the needs of your content management, you might face a lot of pitfalls. For instance, you might loose the link between content and metadata in a database when content moves out of the primary storage.
You see, storage management systems see only file attributes. Without specific instruction, these systems have no idea which files are essential and which are obsolete. In addition, these systems can't update a database after changing the location of files that the database points too.
Having storage management functions built into a content management system can provide potential performance gains associated with fine-tuning storage. If, for example, content comes in many different sizes, files can be directed to RAID systems optimized for large and small files. If it's a subject of active searches, content, such as metadata, can be stored on fast storage while data and inactive content can be placed on near-line storage. Using the available storage more efficiently rather than adding new storage will also provide a gain in scalability.
Some vertical applications might also require that a content management system be able to control storage. For regulatory reasons, you might need to keep financial or medical data on optical storage. A content management system needs to differentiate regulated content and put it in archival storage.
Furthermore, when a content management system directly controls storage, the system is aware of the available storage devices and their capabilities. Systems administrators have the advantage of a single console through which they can manage content and storage at the same time.
Content management systems can also control storage indirectly through a storage management system, but it requires careful investigation and tailoring. The indirect model offers the advantage of the storage management system being available to other applications, and, as a result, lowering storage costs and giving administrators more flexibility.
No matter which option you select, you must think about your storage infrastructure when you set up any content management system. If you expect your system to remain relatively small, then you might get by with separate storage management. If, however, you need the content management system to scale up while maintaining optimal performance, then consider the advantages of tighter integration.