Automated seamless migration with signature issue resolution
An apparatus comprises at least one processing device comprising a processor coupled to a memory. The processing device is configured to control performance of a migration process in which a source logical storage device of a first storage system is migrated to a target logical storage device of a second storage system. In conjunction with the migration process, the processing device is further configured to update a management header of the target logical storage device to include an identifier of the target logical storage device, to store an identifier of the source logical storage device, and responsive to a read of the management header of the target logical storage device, to return the identifier of the source logical storage device in place of the identifier of the target logical storage device. Other illustrative embodiments include methods and computer program products.
1. An apparatus comprising:
at least one processing device comprising a processor coupled to a memory;
said at least one processing device being configured to control performance of a migration process in which a source logical storage device of a first storage system is migrated to a target logical storage device of a second storage system;
wherein in conjunction with the migration process, said at least one processing device is further configured:
to update a management header of the target logical storage device to include an identifier of the target logical storage device,
to store an identifier of the source logical storage device, and
responsive to a read of the management header of the target logical storage device, to return the identifier of the source logical storage device in place of the identifier of the target logical storage device.
2. The apparatus of claim 1 wherein returning the identifier of the source logical storage device in place of the identifier of the target logical storage device resolves a file system signature issue that would otherwise arise if the identifier of the target logical storage device were returned responsive to the read.
3. The apparatus of claim 1 wherein the source logical storage device is one of a plurality of source logical storage devices of a source data store that are migrated to respective target logical storage devices of a target data store in the migration process.
4. The apparatus of claim 1 wherein said at least one processing device comprises a host device that is configured to communicate with the first and second storage systems over a network, the host device implementing a multi-path input-output driver configured to control delivery of input-output operations from the host device to the first and second storage systems over selected paths through the network.
5. The apparatus of claim 4 wherein the multi-path input-output driver is further configured to carry out at least a portion of the migration process.
6. The apparatus of claim 4 wherein the multi-path input-output driver is further configured to perform at least a portion of the updating of the management header, the storing of the identifier of the source logical storage device, and the returning of the identifier of the source logical storage device in place of the identifier of the target logical storage device.
7. The apparatus of claim 4 wherein the target logical storage device is known by its target identifier to the multi-path input-output driver of the host device but is not known by its target identifier to one or more applications executing on the host device, and wherein the multi-path input-output driver is further configured to mediate between the one or more applications and the target logical storage device so as to allow the one or more applications to use the identifier of the source logical storage device in place of the identifier of the target logical storage device even after completion of the migration process.
8. The apparatus of claim 1 wherein the management header of the target logical storage device comprises a logical volume management header located at a designated logical block address of the target logical storage device.
9. The apparatus of claim 1 wherein the management header of the target logical storage device is associated with a file system signature and wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
verifying the file system signature; and
verifying that the management header comprises the identifier of the source logical storage device copied from the source logical storage device in conjunction with the migration process;
wherein the verifying steps are performed prior to updating the management header of the target logical storage device to include the identifier of the target logical storage device.
10. The apparatus of claim 1 wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
reading the identifier of the target logical storage device from the second storage system; and
performing an atomic update operation on the management header to incorporate the identifier of the target logical storage device as read from the second storage system into the management header.
11. The apparatus of claim 10 wherein reading the identifier of the target logical storage device from the second storage system comprises reading the identifier of the target logical storage device by issuing a command to access a designated page of the second storage system containing information characterizing the target logical storage device.
12. The apparatus of claim 1 wherein storing an identifier of the source logical storage device comprises storing a logical volume management header of the source logical storage device in a storage location separate from the target logical storage device and wherein the logical volume management header of the source logical storage device includes the identifier of the source logical storage device.
13. The apparatus of claim 1 wherein the returning of the identifier of the source logical storage device in place of the identifier of the target logical storage device is repeated for each of a plurality of additional reads of the management header of the target logical storage device after completion of the migration process.
14. The apparatus of claim 1 wherein the returning of the identifier of the source logical storage device in place of the identifier of the target logical storage device is repeated for each of a plurality of additional reads of the management header of the target logical storage device until a reboot or remount operation involving a file system of said at least one processing device allows the file system to read the identifier of the target logical storage device from the updated management header of the target logical storage device and to generate a file system signature for the target logical storage device.
15. A method comprising:
controlling performance of a migration process in which a source logical storage device of a first storage system is migrated to a target logical storage device of a second storage system; and
in conjunction with the migration process:
updating a management header of the target logical storage device to include an identifier of the target logical storage device,
storing an identifier of the source logical storage device, and
responsive to a read of the management header of the target logical storage device, returning the identifier of the source logical storage device in place of the identifier of the target logical storage device;
wherein the method is performed by at least one processing device comprising a processor coupled to a memory.
16. The method of claim 15 wherein the management header of the target logical storage device is associated with a file system signature and wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
verifying the file system signature; and
verifying that the management header comprises the identifier of the source logical storage device copied from the source logical storage device in conjunction with the migration process;
wherein the verifying steps are performed prior to updating the management header of the target logical storage device to include the identifier of the target logical storage device.
17. The method of claim 15 wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
reading the identifier of the target logical storage device from the second storage system; and
performing an atomic update operation on the management header to incorporate the identifier of the target logical storage device as read from the second storage system into the management header.
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 at least one processing device comprising a processor coupled to a memory, causes said at least one processing device:
to control performance of a migration process in which a source logical storage device of a first storage system is migrated to a target logical storage device of a second storage system; and
in conjunction with the migration process:
to update a management header of the target logical storage device to include an identifier of the target logical storage device,
to store an identifier of the source logical storage device, and
responsive to a read of the management header of the target logical storage device, to return the identifier of the source logical storage device in place of the identifier of the target logical storage device.
19. The computer program product of claim 18 wherein the management header of the target logical storage device is associated with a file system signature and wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
verifying the file system signature; and
verifying that the management header comprises the identifier of the source logical storage device copied from the source logical storage device in conjunction with the migration process;
wherein the verifying steps are performed prior to updating the management header of the target logical storage device to include the identifier of the target logical storage device.
20. The computer program product of claim 18 wherein updating the management header of the target logical storage device to include the identifier of the target logical storage device comprises:
reading the identifier of the target logical storage device from the second storage system; and
performing an atomic update operation on the management header to incorporate the identifier of the target logical storage device as read from the second storage system into the management header.