Integrated-circuit implementation of a storage-shelf router and a path controller card for combined use in high-availability mass-storage-device shelves and that support virtual disk formatting
View Patent ↗An integrated circuit implementing a storage-shelf router used alone, or in combination with other storage-shelf routers, and in combination with path controller cards, to interconnect the disks within a storage shelf or disk array to a high-bandwidth communications medium through which data is exchanged between the individual disk drives of the storage shelf and a disk-array controller. In various embodiments, the present invention provides virtual disk formatting by a storage shelf router and the storage shelf in which the storage-shelf is included, to external computing entities, such as disk-array controllers and host computers. By providing virtual disk formatting, a storage-shelf router can provide to a disk-array controller, and other external computing entities, the disk-formatting convention expected by the disk-array controller, even though disk drives and other storage systems that do not conform to the expected formatting conventions may be included in the storage shelf and interconnected to a disk-array controller and other external processing entities via an interface provided by a storage-shelf router. Virtual disk formatting, in addition, allows a storage-shelf router to format a disk drive differently from the disk formatting expected by external computing entities, so that the storage-shelf router can transparently include additional information into disk sectors, such as additional error detection and error-correction information.
1. A virtual disk formatting system comprising:
a plurality of mass-storage devices having physical sectors of a first sector length; and
a routing component that provides to external entities a first virtual disk interface to the mass-storage components by mapping each access operation, received from one of the external entities, directed to the first virtual disk interface having virtual sectors of a second sector length to an internal, virtual disk interface with internal-virtual-disk-sectors having a third sector length larger than the second sector length, and then routing the access operations from the internal, virtual disk interface to one or more mass-storage devices of the plurality of mass-storage devices;
wherein the first sector length and the second sector length refer to data-payload lengths of physical sectors.
2. A virtual disk formatting system of claim 1 further including:
including, by the routing component, error detection information within the internal-virtual-disk-interface sectors in order to provide routing-component-mediated error checking.
3. The virtual disk formatting system of claim 2 wherein the error detection information is a longitudinal redundancy check code.
4. The virtual disk formatting system of claim 1 wherein the routing component is an integrated-circuit storage-shelf router.
5. The virtual disk formatting system of claim 4 wherein the storage-shelf router provides a fibre-channel-disk-based virtual disk formatting interface to external processing entities and maps fibre-channel-disk-based access operations to a number of ATA disk drives included in a storage shelf containing the storage-shelf router.
6. The virtual routing system of claim 1 wherein the routing component includes a processor and firmware/software programs that carry out virtual disk formatting.
7. A method for including additional information in disk sectors of a plurality of mass-storage devices having a first sector length, the method comprising:
providing a routing component;
mapping, by the routing component, access operations, received from one of the external entities, directed to a first virtual disk interface having virtual sectors of a second sector length to an internal, virtual disk interface with internal-virtual-disk-sectors having a third sector length larger than the second sector length, and then routing, by the routing component, the access operations from the internal, virtual disk interface to one or more of the plurality of mass-storage devices;
wherein the first sector length and the second sector length refer to data-payload lengths of physical sectors.
8. The method of claim 7 further including:
including, by the routing component, within the internal-virtual-disk-interface sectors one of:
error-detection information;
additional information that, together with the data contained in the internal-virtual-disk-interface sectors, provides an encrypted version of the data directed to the first virtual disk interface by external processing entities; and
error-detection and error-correction information.