Non-disruptive transformation of a logical storage device from a first access protocol to a second access protocol

1. An apparatus comprising:

a host device comprising a processor coupled to a memory;

the host device being configured to communicate over a network with a storage system;

the host device being further configured:

to discover one or more first protocol endpoints presented by the storage system for a first logical storage device, the first logical storage device utilizing a first access protocol;

to discover one or more second protocol endpoints presented by the storage system for a second logical storage device, the second logical storage device utilizing a second access protocol different than the first access protocol;

responsive to determining that the first and second logical storage devices have a same device identity, to temporarily mask the one or more second protocol endpoints in a multi-path layer of the host device from one or more applications executing on the host device; and

in conjunction with a switchover from the first logical storage device to the second logical storage device, to end the temporary masking in the multi-path layer and to enable access of the one or more applications to the second logical storage device via the one or more second protocol endpoints.

2. The apparatus of claim 1 wherein the first access protocol comprises a Small Computer System Interface (SCSI) access protocol and the second access protocol comprises a Non-Volatile Memory Express (NVMe) access protocol, and wherein the first logical storage device is configured by the storage system as a SCSI storage device and the second logical storage device is configured by the storage system as an NVMe storage device having the same device identity as the first logical storage device.

3. The apparatus of claim 1 wherein the first and second logical storage devices are part of a same storage pool of a storage array of the storage system.

4. The apparatus of claim 1 wherein the first and second logical storage devices are part of respective first and second different storage pools of at least one storage array of the storage system.

5. The apparatus of claim 4 wherein the first and second logical storage devices are part of respective first and second different storage pools of respective first and second storage arrays of the storage system.

6. The apparatus of claim 4 wherein prior to initiation of the switchover from the first logical storage device to the second logical storage device, data is copied from the first logical storage device in the first storage pool to the second logical storage device in the second storage pool.

7. The apparatus of claim 1 wherein the multi-path layer comprises at least one multi-path input-output driver configured to control delivery of input-output operations from the host device to the storage system over one or more selected paths through the network.

8. The apparatus of claim 1 wherein in conjunction with discovering one or more first protocol endpoints and one or more second protocol endpoints, the host device is further configured:

to determine a first set of paths for accessing the first logical storage device via the one or more first protocol endpoints; and

to determine a second set of paths for accessing the second logical storage device via the one or more second protocol endpoints.

9. The apparatus of claim 8 wherein the first and second sets of paths are managed by the multi-path layer utilizing respective first and second class objects implemented as respective first and second loadable array modules.

10. The apparatus of claim 1 wherein temporarily masking the one or more second protocol endpoints in the multi-path layer of the host device from one or more applications executing on the host device comprises interrupting a process for publishing the one or more second protocol endpoints from the multi-path layer to at least a portion of at least one host device layer above the multi-path layer.

11. The apparatus of claim 10 wherein ending the temporary masking in the multi-path layer comprises performing the process for publishing the one or more second protocol endpoints from the multi-path layer to the at least a portion of the at least one host device layer above the multi-path layer.

12. The apparatus of claim 1 wherein the one or more first protocol endpoints presented by the storage system for the first logical storage device are presented via a translation layer of the storage system that translates from a third access protocol to the first access protocol.

13. The apparatus of claim 12 wherein the third access protocol comprises a Non-Volatile Memory Express over Fabric (NVMeoF) access protocol.

14. The apparatus of claim 1 wherein responsive to determining that the first and second logical storage devices have a same device identity the multi-path layer merges the first and second logical storage devices into a single pseudo device for presentation to the one or more applications executing on the host device.

15. A method performed by a host device configured to communicate over a network with a storage system, comprising:

discovering one or more first protocol endpoints presented by the storage system for a first logical storage device, the first logical storage device utilizing a first access protocol;

discovering one or more second protocol endpoints presented by the storage system for a second logical storage device, the second logical storage device utilizing a second access protocol different than the first access protocol;

responsive to determining that the first and second logical storage devices have a same device identity, temporarily masking the one or more second protocol endpoints in a multi-path layer of the host device from one or more applications executing on the host device; and

in conjunction with a switchover from the first logical storage device to the second logical storage device, ending the temporary masking in the multi-path layer and enabling access of the one or more applications to the second logical storage device via the one or more second protocol endpoints;

wherein the host device comprises a processor coupled to a memory.

16. The method of claim 15 wherein in conjunction with discovering one or more first protocol endpoints and one or more second protocol endpoints, the host device is further configured:

to determine a first set of paths for accessing the first logical storage device via the one or more first protocol endpoints; and

to determine a second set of paths for accessing the second logical storage device via the one or more second protocol endpoints.

17. The method of claim 15 wherein temporarily masking the one or more second protocol endpoints in the multi-path layer of the host device from one or more applications executing on the host device comprises interrupting a process for publishing the one or more second protocol endpoints from the multi-path layer to at least a portion of at least one host device layer above the multi-path layer.

18. A computer program product comprising a non-transitory processor-readable storage medium having stored therein program code of one or more software programs, wherein the program code, when executed by a host device comprising a processor coupled to a memory and configured to communicate over a network with a storage system, causes the host device:

to discover one or more first protocol endpoints presented by the storage system for a first logical storage device, the first logical storage device utilizing a first access protocol;

to discover one or more second protocol endpoints presented by the storage system for a second logical storage device, the second logical storage device utilizing a second access protocol different than the first access protocol;

responsive to determining that the first and second logical storage devices have a same device identity, to temporarily mask the one or more second protocol endpoints in a multi-path layer of the host device from one or more applications executing on the host device; and

in conjunction with a switchover from the first logical storage device to the second logical storage device, to end the temporary masking in the multi-path layer and to enable access of the one or more applications to the second logical storage device via the one or more second protocol endpoints.

19. The computer program product of claim 18 wherein in conjunction with discovering one or more first protocol endpoints and one or more second protocol endpoints, the host device is further configured:

to determine a first set of paths for accessing the first logical storage device via the one or more first protocol endpoints; and

to determine a second set of paths for accessing the second logical storage device via the one or more second protocol endpoints.

20. The computer program product of claim 18 wherein temporarily masking the one or more second protocol endpoints in the multi-path layer of the host device from one or more applications executing on the host device comprises interrupting a process for publishing the one or more second protocol endpoints from the multi-path layer to at least a portion of at least one host device layer above the multi-path layer.