Storage router and method for providing virtual local storage
A storage router and method for providing virtual local storage on remote storage devices to devices are provided. Devices are connected to a first transport medium, and a plurality of storage devices are connected to a second transport medium. In one embodiment, the storage router maintains a map to allocate storage space on the remote storage devices to devices connected to the first transport medium by associating representations of the devices connected to the first transport medium with representations of storage space on the remote storage devices, wherein each representation of a device connected to the first transport medium is associated with one or more representations of storage space on the remote storage devices. The storage router can control access from the devices connected to the first transport medium to the storage space on the remote storage devices in accordance with the access controls.
1. A storage router for providing virtual local storage on remote storage devices, comprising:
a first controller operable to interface with a first transport medium, wherein the first transport medium is a serial network transport medium;
a second controller operable to interface with a second transport medium; and
a processing device coupled to the first controller, wherein the processing device is configured to:
maintain a map to allocate storage space on the remote storage devices connected to the second transport medium to devices connected to the first transport medium as a common single transport medium by associating representations of the devices connected to the first transport medium with representations of storage space on the remote storage devices, wherein each representation of a device connected to the first transport medium comprises a unique identifier that distinguishes a corresponding device from others of the devices connected to the first transport medium, wherein the map resides at the storage router and wherein the storage router is configurable to allocate a first subset of the storage space to a set of devices connected to the first transport medium as storage shared by the set of devices and allocate a second subset of the storage space to a subset of the set of devices connected to the first transport medium;
provide centralized access controls at the storage router to control access by the devices connected to the first transport medium to the storage space on the remote storage devices, wherein the map is used to control access;
allow access from the devices connected to the storage router through the first transport medium to the remote storage devices according to the centralized access controls; and
receive native low level block protocol requests from the devices connected to the first transport medium to access the remote storage devices.
2. The storage router of claim 1 , wherein the map associates a representation of storage space on the remote storage devices with representations of multiple devices connected to the first transport medium.
3. The storage router of claim 1 , wherein the storage space on the remote storage devices comprises storage space on multiple remote storage devices.
4. The storage router of claim 1 , wherein the map associates a representation of a device connected to the first transport medium with a representation of an entire storage space of at least one remote storage device.
5. The storage router of claim 1 , wherein the storage router is configured to receive commands according to a first low level block protocol from devices connected to the first transport medium and forward commands according to a second low level block protocol to the remote storage devices.
6. The storage router of claim 1 , wherein the map comprises one or more tables.
7. The storage router of claim 1 , wherein the virtual local storage is provided to the devices connected to the first transport medium in a manner that is transparent to the devices and wherein the storage space allocated to the devices connected to the first transport medium appears to the devices as local storage.
8. The storage router of claim 1 , wherein the storage router provides centralized control of what the devices connected to the first transport medium see as local storage.
9. The storage router of claim 1 , wherein the representations of storage space comprise logical unit numbers that represent a subset of storage on the remote storage devices.
10. The storage router of claim 9 , wherein the storage router is operable to route requests to the same logical unit number from different devices connected to the first transport medium to different subsets of storage space on the remote storage devices.
11. The storage router of claim 1 , wherein the unique identifiers are world wide names.
12. The storage router of claim 11 , wherein the storage router is configured to allow modification of the map in a manner transparent to and without involvement of the devices connected to the first transport medium.
13. The storage router of claim 1 , wherein the processing device is a microprocessor.
14. The storage router of claim 1 , wherein the processing device is a microprocessor and associated logic to implement a stand-alone processing system.
15. The storage router of claim 1 , wherein the first transport medium is a first fibre channel transport medium and the second transport medium is a second fibre channel transport medium.
16. The storage router of claim 1 , wherein at least one of the devices connected to the first transport medium is a network server.
17. A method for providing virtual local storage on remote storage devices comprising:
connecting a storage router between devices connected to a first transport medium as a common single transport medium and the remote storage devices, wherein the first transport medium is a serial network transport medium and the remote storage devices are connected to the second transport medium;
maintaining a map to allocate storage space on the remote storage devices to devices connected to the first transport medium by associating representations of the devices connected to the first transport medium with representations of storage space on the remote storage devices, wherein each representation of a device connected to the first transport medium comprises a unique identifier that distinguishes a corresponding device from others of the devices connected to the first transport medium, wherein the map resides at the storage router and wherein the storage router is configurable to allocate a first subset of the storage space to a set of devices connected to the first transport medium as shared storage and allocate a second subset of the storage space to a subset of the set of devices connected to the first transport medium;
providing centralized access controls at the storage router to control access by the devices connected to the first transport medium to the storage space on the remote storage devices, wherein the map is used to control access;
allowing access from the devices connected to the first transport medium to the remote storage devices; and
receiving native low level block protocol requests from the devices connected to the first transport medium to access the remote storage devices.
18. The method of claim 17 , wherein the storage space on the remote storage devices comprises storage space on multiple remote storage devices.
19. The method of claim 17 , wherein the map associates a representation of a device connected to the first transport medium with a representation of an entire storage space of at least one remote storage device.
20. The method of claim 17 , further comprising receiving commands at the storage router according to a first low level block protocol from the device connected to the first transport medium and forwarding commands according to a second low level block protocol to the remote storage devices.
21. The method of claim 17 , wherein the map comprises one or more tables.
22. The method of claim 17 , wherein the virtual local storage is provided to the devices connected to the first transport medium in a manner that is transparent to the devices and wherein the storage space allocated to the devices connected to the first transport medium appears to the devices as local storage.
23. The method of claim 17 , wherein the storage router provides centralized control of what the devices connected to the first transport medium see as local storage.
24. The method of claim 17 , wherein the representations of storage space comprise logical unit numbers that represent a subset of storage on the remote storage devices.
25. The method of claim 24 , wherein the storage router is operable to route requests to the same logical unit number from different devices connected to the first transport medium to different subsets of storage space on the remote storage devices.
26. The method of claim 17 , wherein the unique identifiers are world wide names.
27. The method of claim 26 , wherein the storage router is configured to allow modification of the map in a manner transparent to and without involvement of the devices connected to the first transport medium.
28. The method of claim 17 , wherein connecting a storage router between the first transport medium and storage devices further comprises connecting the storage router between a first fibre channel transport medium and a second fibre channel transport medium.