Efficient migration of logical storage devices without requiring initial application reconfiguration
An apparatus in an illustrative embodiment implements a proxy device for a first logical storage device. The proxy device inserts tags into respective received input-output (IO) operations before directing those IO operations to the first logical storage device. The apparatus further implements a mirror device to provide a mirroring arrangement between the proxy device and a second logical storage device. In addition, the apparatus checks, in an entry point associated with the first logical storage device, each IO operation directed to the first logical storage device for a tag inserted by the proxy device. The apparatus provides, from the entry point to the first logical storage device, any received IO operations that have the tag. Furthermore, the apparatus redirects, from the entry point to the mirror device providing the mirroring arrangement, any received IO operations that do not have the tag.
1. An apparatus comprising:
at least one processing device comprising a processor coupled to a memory;
the at least one processing device being configured, in conjunction with migration of data from a first logical storage device to a second logical storage device:
to implement a proxy device for the first logical storage device, the proxy device being configured to insert tags into respective received input-output operations before directing those input-output operations to the first logical storage device;
to implement a mirror device to provide a mirroring arrangement between the proxy device and the second logical storage device;
to check, in an entry point associated with the first logical storage device, each input-output operation directed to the first logical storage device for a tag inserted by the proxy device;
to provide, from the entry point to the first logical storage device, any received input-output operations that have the tag; and
to redirect, from the entry point to the mirror device, any received input-output operations that do not have the tag.
2. The apparatus of claim 1 wherein the at least one processing device comprises at least a portion of a host device configured to communicate with a storage system over a network.
3. The apparatus of claim 2 wherein said at least one processing device comprises a multi-path input-output driver of the host device, with the multi-path input-output driver of the host device being configured to control delivery of input-output operations from the host device to the storage system over selected ones of a plurality of paths through the network and to perform at least a portion of the migration of data from the first logical storage device to the second logical storage device.
4. The apparatus of claim 3 wherein the multi-path input-output driver of the host device comprises a device mapper multi-path input-output driver operating in a Linux native multi-pathing environment.
5. The apparatus of claim 2 wherein the first and second logical storage devices comprise respective Linux block devices associated with a same storage array of the storage system.
6. The apparatus of claim 2 wherein the first and second logical storage devices comprise respective Linux block devices associated with distinct first and second storage arrays of the storage system.
7. The apparatus of claim 1 wherein the at least one processing device is further configured to temporarily suspend input-output operations targeting the first logical storage device in conjunction with implementation of the proxy device and the mirror device.
8. The apparatus of claim 7 wherein the temporary suspension of the input-output operations targeting the first logical storage device is released responsive to implementation of the proxy device and the mirror device and configuration of the entry point of the first logical storage device to check for the tag inserted by the proxy device.
9. The apparatus of claim 1 wherein the at least one processing device is further configured, responsive to detection of a designated synchronization condition between the first logical storage device and the second logical storage device, to deactivate the mirror device and the proxy device and to modify the entry point associated with the first logical storage device to redirect all received input-output operations to the second logical storage device.
10. The apparatus of claim 1 wherein, responsive to successful completion of the migration, at least one application is reconfigured to utilize the second logical storage device in place of the first logical storage device.
11. The apparatus of claim 1 wherein the proxy device comprises a dummy block device implemented using a loop device.
12. 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 the at least one processing device to perform a method for migrating data of a first logical storage device to a second logical storage device, the method comprising:
implementing a proxy device for the first logical storage device, the proxy device being configured to insert tags into respective received input-output operations before directing those input-output operations to the first logical storage device;
implementing a mirror device to provide a mirroring arrangement between the proxy device and the second logical storage device;
checking, in an entry point associated with the first logical storage device, each input-output operation directed to the first logical storage device for a tag inserted by the proxy device;
providing, from the entry point to the first logical storage device, any received input-output operations that have the tag; and
redirecting, from the entry point to the mirror device, any received input-output operations that do not have the tag.
13. The computer program product of claim 12 wherein, responsive to detection of a designated synchronization condition between the first logical storage device and the second logical storage device, the mirror device and the proxy device are deactivated and the entry point associated with the first logical storage device is modified to redirect all received input-output operations to the second logical storage device.
14. The computer program product of claim 12 wherein, responsive to successful completion of the migration, at least one application is reconfigured to utilize the second logical storage device in place of the first logical storage device.
15. The computer program product of claim 12 wherein the proxy device comprises a dummy block device implemented using a loop device.
16. A method for migrating data of a first logical storage device to a second logical storage device, the method comprising:
implementing a proxy device for the first logical storage device, the proxy device being configured to insert tags into respective received input-output operations before directing those input-output operations to the first logical storage device;
implementing a mirror device to provide a mirroring arrangement between the proxy device and the second logical storage device;
checking, in an entry point associated with the first logical storage device, each input-output operation directed to the first logical storage device for a tag inserted by the proxy device;
providing, from the entry point to the first logical storage device, any received input-output operations that have the tag; and
redirecting, from the entry point to the mirror device, any received input-output operations that do not have the tag.
17. The method of claim 16 wherein the migration of data from the first logical storage device to the second logical storage device is performed without requiring any initial reconfiguration of one or more applications that generate the input-output operations.
18. The method of claim 16 wherein, responsive to detection of a designated synchronization condition between the first logical storage device and the second logical storage device, the mirror device and the proxy device are deactivated and the entry point associated with the first logical storage device is modified to redirect all received input-output operations to the second logical storage device.
19. The method of claim 16 wherein, responsive to successful completion of the migration, at least one application is reconfigured to utilize the second logical storage device in place of the first logical storage device.
20. The method of claim 16 wherein the proxy device comprises a dummy block device implemented using a loop device.