Granted Patent B2

US 6,865,617 · App. 09/862,514 · Granted Mar 8, 2005

Abstract

Claims (80)

1. A method of mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising the steps of:

(a) transmitting, from the initiator, a registration command via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number;

(b) establishing a mapping, responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) transmitting, from the initiator, a SCSI data transfer command, the SCSI data transfer command indicating the multicast group address;

(d) receiving, at each of the members of the multicast group, the data transfer command, and transferring data in response thereto;

(e) executing, in each of the SCSI members of the multicast group, the specified data transfer command.

2. The method of claim 1 , further comprising the step of:

(f) transmitting, from the initiator, to each target of the plurality of targets, a mirroring termination command.

3. The method of claim 2 , wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

4. The method of claim 2 , wherein the mirroring termination command causes a disassociation from the multicast group.

5. The method of claim 2 , wherein each target of the plurality of targets returns, to the initiator, a status indicating completion of the mirroring termination command.

6. The method of claim 1 , wherein the data transfer command is a WRITE command.

7. The method of claim 6 , wherein the WRITE command specifies the virtual logical unit number.

8. The method of claim 6 , wherein there are a plurality of WRITE commands.

9. The method of claim 1 , wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets.

10. The method of claim 1 , wherein the registration command has a standard SCSI text command format.

11. The method of claim 1 , wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device.

12. The method of claim 1 , wherein, upon establishing the mapping, each target of the plurality of targets returns a message to the initiator.

13. The method of claim 1 , wherein the data transfer command is transmitted via a multicast.

14. The method of claim 1 , wherein each of the SCSI members of the multicast group returns a status of the data transfer command, and wherein the initiator handles any error status of the data transfer command.

15. A method of mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising the steps of:

(a) transmitting, from the initiator, a registration command via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number, wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets, wherein the registration command has a standard SCSI text command format, and wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device;

(b) establishing a mapping, responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) transmitting, from the initiator, a SCSI data transfer command, the SCSI data transfer command indicating the multicast group address, wherein the data transfer command is a WRITE command, and wherein the WRITE command specifies the virtual logical unit number;

(d) receiving, at each of the members of the multicast group, the data transfer command, and transferring data in response thereto;

(e) executing, in each of the SCSI members of the multicast group, the specified data transfer command; and

(f) transmitting, from the initiator, to each target of the plurality of targets, a mirroring termination command, wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

16. A system for mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising:

(a) a registration command, transmitted from the initiator via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number;

(b) a mapping, established responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) a SCSI data transfer command, transmitted from the initiator, the SCSI data transfer command indicating the multicast group address; and

(d) at each of the members of the multicast group, responsive to reception of the data transfer command, a transfer of data.

17. The system of claim 16 , further comprising:

(f) a mirroring termination command, transmitted, from the initiator, to each target of the plurality of targets.

18. The system of claim 17 , wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

19. The system of claim 17 , wherein the mirroring termination command causes a disassociation from the multicast group.

20. The system of claim 17 , wherein each target of the plurality of targets returns, to the initiator, a status indicating completion of the mirroring termination command.

21. The system of claim 16 , wherein the data transfer command is a WRITE command.

22. The system of claim 21 , wherein the WRITE command specifies the virtual logical unit number.

23. The system of claim 21 , wherein there are a plurality of WRITE commands.

24. The system of claim 16 , wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets.

25. The system of claim 16 , wherein the registration command has a standard SCSI text command format.

26. The system of claim 16 , wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device.

27. The system of claim 16 , wherein, upon establishing the mapping, each target of the plurality of targets returns a message to the initiator.

28. The system of claim 16 , wherein the data transfer command is transmitted via a multicast.

29. The system of claim 16 , wherein each of the SCSI members of the multicast group returns a status of the data transfer command, and wherein the initiator handles any error status of the data transfer command.

30. The system of claim 16 , wherein each command is embodied as an electronic signal.

31. A system of mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising:

(a) a registration command transmitted from the initiator via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number, wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets, wherein the registration command has a standard SCSI text command format, and wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device;

(b) a mapping, established responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) a SCSI data transfer command, transmitted from the initiator, the SCSI data transfer command indicating the multicast group address, wherein the data transfer command is a WRITE command, and wherein the WRITE command specifies the virtual logical unit number;

(d) at each of the members of the multicast group, a received data transfer command, and transferring data in response thereto; and

(e) a mirroring termination command transmitted from the initiator to each target of the plurality of targets, wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

32. A system ofor mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising:

(a) means for transmitting, from the initiator, a registration command via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number;

(b) means for establishing a mapping, responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) means for transmitting, from the initiator, a SCSI data transfer command, the SCSI data transfer command indicating the multicast group address;

(d) means for receiving, at each of the members of the multicast group, the data transfer command, and transferring data in response thereto; and

(e) means for executing, in each of the SCSI members of the multicast group, the specified data transfer command.

33. The system of claim 32 , further comprising:

(f) means for transmitting, from the initiator, to each target of the plurality of targets, a mirroring termination command.

34. The system of claim 33 , wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

35. The system of claim 33 , wherein the mirroring termination command causes a disassociation from the multicast group.

36. The system of claim 33 , wherein each target of the plurality of targets returns, to the initiator, a status indicating completion of the mirroring termination command.

37. The system of claim 32 , wherein the data transfer command is a WRITE command.

38. The system of claim 37 , wherein the WRITE command specifies the virtual logical unit number.

39. The system of claim 37 , wherein there are a plurality of WRITE commands.

40. The system of claim 32 , wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets.

41. The system of claim 32 , wherein the registration command has a standard SCSI text command format.

42. The system of claim 32 , wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device.

43. The system of claim 32 , wherein, upon establishing the mapping, each target of the plurality of targets returns a message to the initiator.

44. The system of claim 32 , wherein the data transfer command is transmitted via a multicast.

45. The system of claim 32 , wherein each of the SCSI members of the multicast group returns a status of the data transfer command, and wherein the initiator handles any error status of the data transfer command.

46. A system for mirroring data transfer commands in a network, the network including a SCSI initiator and a plurality of SCSI targets, the initiator and targets all being connected to a TCP/IP network, comprising:

(a) means for transmitting, from the initiator, a registration command via the TCP/IP network, to each target of the plurality of targets, the registration command including a multicast address and a virtual logical unit number, wherein the registration command is transmitted to a unicast address corresponding to each target of the plurality of targets, wherein the registration command has a standard SCSI text command format, and wherein each target of the plurality of targets responds to the registration command by setting a communication NIC to listen on the multicast address; and by mapping the virtual logical unit number to the SCSI device;

(b) means for establishing a mapping, responsive to the registration command, at each of the SCSI devices, indicating an association between the SCSI device and the virtual logical unit number and the multicast address;

(c) means for transmitting, from the initiator, a SCSI data transfer command, the SCSI data transfer command indicating the multicast group address, wherein the data transfer command is a WRITE command, and wherein the WRITE command specifies the virtual logical unit number;

(d) means for receiving, at each of the members of the multicast group, the data transfer command, and transferring data in response thereto;

(e) means for executing, in each of the SCSI members of the multicast group, the specified data transfer command; and

(f) means for transmitting, from the initiator, to each target of the plurality of targets, a mirroring termination command, wherein the mirroring termination command causes a disassociation from the virtual logical unit number.

Assignments (11)