What is storage management? Is it simply backup and recovery? Is it the monitoring of the storage and networking elements in data path for failure and, perhaps performance? Is it managing the data that is located out on the storage elements (tape, disk, etc)? Is it setting up RAID levels and monitoring capacity? Storage management is all of these and every storage management plan, and ideally the storage management software, should address each of these aspects.
There are three logical aspects to storage management: device management, access management and content management. Device management encompasses the management of the physical devices and their attachments. This is where you would configure the RAID level of a disk, collect alerts and alarms about the health of the devices and keep track of what level of software/firmware is currently installed on the devices. It also includes the management of the physical connectivity elements of the data path, whether they are, SCSI cables, Fibre Channel (or ESCON) networks, or IP networks.
Access management covers two management areas. The first area is the management of how an application gains access to storage and data. Accessibility must be addressed at every level of the data path. At the lowest level, it includes logical unit number (LUN) partitioning of the storage devices. Moving up a level is managing the interface between the operating system and the storage. Which LUNs will be accessed by which drivers then, which file systems will correspond to those LUNs. Also included in access management are the data paths to the storage connections or network. In a SCSI environment, path management is fairly simple. However, path management in a networked environment can be quite complex, especially when managing a high-availability environment with no single point of failure.
The second area associated with access management is security.
Who is allowed to access the storage? This includes hosts, appliances, switches, etc. One can choose to also include user and application security, or access through the operating system whether it is via a file system or directly by an application (as many databases do) within storage access management as it is tightly coupled with physical access management.
Finally, there is storage content management, which covers every aspect of the data stored on the storage media. In the case of the disk, content management includes the protection of the data via replication to other media whether it's another disk subsystem or backup and recovery to tape, monitoring user and total capacity, filtering data for unwanted/outdated data, and enforcing policy given the state of the content and the business requirements. In the case of tape, content management allows for correct and timely access to the data located on the tape media, often interacting with disk management capabilities.
All aspects of storage management should be integrated into a common plan for best practices within your organization, no matter the size of the organization. As you can see, storage management can be quite complex. Unfortunately, there are very few companies that offer storage management software with all these aspects integrated into one package, but there are some that come close such as Veritas, BMC and Computer Associates.
If all else fails, there are many point products available that can be used with the common integration point being HP OpenView, CA Unicenter, Tivoli or similar management umbrellas.
Due to the complexity of the problem, many smaller companies have chosen to focus on one aspect of the storage management problem to provide excellent customer value in that area. Some of those companies include InterSan, Legato, StorageNetworks and Finisar.