Data storage systems include provisions for housing and managing one or more physical storage devices and making storage space on the installed storage devices available to one or more data-connected user computers. A storage system that includes multiple storage devices is sometimes referred to as a storage “array.” A storage array may have bays or slots in which storage devices can be installed. A storage array may support one or more types of storage device (e.g., magnetic disk drives, optical disk drives, solid state storage such as flash and USB drives, tape drives, etc.). The DROBO™ data storage system available from Data Robotics, Inc., Santa Clara, Calif., is an example of a storage array having slots for multiple storage devices (specifically disk drives). Typically, the cumulative storage space of all the storage devices (less space used for overhead and redundancy) is made to appear to the user computers as a single virtual disk. Storage systems control the installed storage devices and manage the storage capacity provided by the installed storage devices. For example, some data storage systems may store data redundantly on two or more of the installed storage devices, in case one of the storage devices fails.
Auxiliary applications, sometimes referred to as “dashboard” applications, provide user interfaces to data storage systems. For example, a dashboard application may provide a graphical display, such as a pie chart, that indicates how the storage space on the storage devices is currently being used, i.e., the amount of storage space that is currently free, reserved for expansion, used for protection (data redundancy) and used for overhead. A dashboard application may be executed by a user computer that is connected to a data storage system via a wired or wireless computer network, a universal serial bus (USB) cable, or the like.
Many such data storage systems are designed to be used by unsophisticated users. For example, a data storage system may be configured such that storage devices may be added to or removed from the data storage system by a user without use of tools, without powering down the data storage system or the user computer, and without the user interacting with any management software. A user may increase the total amount of storage space in the data storage system simply by sliding an additional storage device into an available slot or by replacing an existing storage device with a larger capacity storage device. Similarly, a user may replace a failed storage device with a replacement storage device.
Software in the data storage system automatically detects the insertion and removal of storage devices. In response, the software formats newly inserted storage devices, copies data to storage devices that have been inserted to replace failed storage devices, etc. Thus, the user may treat the data storage system as a storage “appliance,” without understanding or managing its operation. The user may treat physical storage devices as commodities having stated capacities.
Despite being able to be treated as simple replaceable commodities, storage devices are actually quite complex devices that include sophisticated electronic and/or electromechanical subsystems, including processors and firmware. Occasionally, a manufacturer inadvertently releases a batch of flawed storage devices. For example, a flaw may involve a mismatch between firmware installed on a disk drive and an electronic or mechanical component in the disk drive. Such a disk drive may fail or it may cause other problems if used in a data storage system.
Unfortunately, unsophisticated users of data storage systems typically do not monitor release notes or check for product recalls issued by storage device manufacturers. Such a user is not likely to understand the significance of a flaw or the importance of resolving a flaw-related issue with a storage device. Even if a user of a data storage system were to become aware of a flaw in one of his/her storage devices, the user is unlikely to be technically versed enough to resolve the issue, which may involve obtaining revised firmware from the storage device manufacturer and installing the revised firmware in the storage device. Furthermore, data storage systems are typically marketed to users who prefer not to manage their systems. Consequently, issues related to flawed storage devices are likely to go unresolved and may cause catastrophic data loss or other problems within data storage systems.