Dynamic configuration of logical storage devices accessible across multiple storage systems
An apparatus in one embodiment includes at least one processing device comprising a processor coupled to a memory. The at least one processing device is configured to identify a logical storage device accessible in at least first and second storage systems, to measure response times for accessing the logical storage device in each of the first and second storage systems, and to modify, based at least in part on the measured response times, asymmetric access state settings for the logical storage device. Modifying asymmetric access state settings for the logical storage device in some embodiments illustratively comprises modifying asymmetric logical unit access (ALUA) or asymmetric namespace access (ANA) state settings for the logical storage device. Such modifications are illustratively performed in a dynamic manner that responds to variations in the measured response times so as to facilitate load balancing across storage controllers of the first and second storage systems.
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 identify a logical storage device accessible in at least first and second storage systems;
to measure response times for accessing the logical storage device in each of the first and second storage systems; and
to modify, based at least in part on the measured response times, asymmetric access state settings for the logical storage device;
wherein measuring response times for accessing the logical storage device in each of the first and second storage systems comprises sending one or more commands from a host device to each of the first and second storage systems, receiving responses to each of the one or more commands in the host device from each of the first and second storage systems, comparing in the host device the responses received from the first and second storage systems, the responses including at least a first response received from the first storage system and a second response received from the second storage system, and identifying in the host device that the host device is configured as an equidistant host device relative to the first and second storage systems, based at least in part on a result of the comparing of the responses from the first and second storage systems, by the host device, indicating that the first and second storage systems are less than a threshold distance apart from one another, wherein the comparing of the responses includes computing in the host device a computed distance between the first and second storage systems, based at least in part on the responses, and comparing the computed distance to the threshold distance, and wherein the modifying of the asymmetric access state settings for the logical storage device is performed responsive to the computed distance being less than the threshold distance.
2. The apparatus of claim 1 wherein said at least one processing device comprises at least a portion of a host device.
3. The apparatus of claim 1 wherein the first and second storage systems are arranged in an active-active configuration relative to one another.
4. The apparatus of claim 1 wherein the logical storage device comprises a metro/stretched logical storage volume.
5. The apparatus of claim 1 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric logical unit access (ALUA) state settings for the logical storage device.
6. The apparatus of claim 1 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric namespace access (ANA) state settings for the logical storage device.
7. The apparatus of claim 1 wherein said at least one processing device further comprises a multi-path layer that includes at least one multi-path input-output driver configured to control delivery of input-output operations from a host device to the first and second storage systems over selected paths through a network over which the host device communicates with the first and second storage systems.
8. The apparatus of claim 7 wherein the logical storage device is accessible to the multi-path layer via one or more first sets of paths to the first storage system and one or more second sets of paths to the second storage system.
9. The apparatus of claim 7 wherein the multi-path input-output driver is configured to send one or more commands to each of the first and second storage systems and to process corresponding command responses from the first and second storage systems, and to determine, based at least in part on a difference between at least one response time for the first storage system and at least one response time for the second storage system, whether or not the host device is configured as an equidistant host device relative to the first and second storage systems.
10. The apparatus of claim 1 wherein modifying asymmetric access state settings for the logical storage device comprises modifying an asymmetric access state for each of one or more storage controllers of each of the first and second storage systems from an active-optimized (AO) state to an active-non-optimized (ANO) state or vice versa.
11. The apparatus of claim 10 wherein each of the storage controllers has at least one port associated therewith in its corresponding one of the first and second storage systems.
12. The apparatus of claim 10 wherein modifying asymmetric access state settings for the logical storage device comprises modifying the asymmetric access states of respective first and second storage controllers of the first storage system from respective AO and ANO states to respective ANO and ANO states, and modifying the asymmetric access state of respective first and second storage controllers of the second storage system from respective ANO and ANO states to respective AO and ANO states.
13. The apparatus of claim 10 wherein said at least one processing device is further configured to perform path selection in a manner that favors accessing the logical storage device via paths to a storage controller having an AO state over paths to a storage controller having an ANO state.
14. The apparatus of claim 1 wherein measuring response times for accessing the logical storage device in each of the first and second storage systems comprises collecting response time measurements for respective input-output operations directed to the logical storage device over a designated period of time.
15. 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 identify a logical storage device accessible in at least first and second storage systems;
to measure response times for accessing the logical storage device in each of the first and second storage systems; and
to modify, based at least in part on the measured response times, asymmetric access state settings for the logical storage device;
wherein measuring response times for accessing the logical storage device in each of the first and second storage systems comprises sending one or more commands from a host device to each of the first and second storage systems, receiving responses to each of the one or more commands in the host device from each of the first and second storage systems, comparing in the host device the responses received from the first and second storage systems, the responses including at least a first response received from the first storage system and a second response received from the second storage system, and identifying in the host device that the host device is configured as an equidistant host device relative to the first and second storage systems, based at least in part on a result of the comparing of the responses from the first and second storage systems, by the host device, indicating that the first and second storage systems are less than a threshold distance apart from one another, wherein the comparing of the responses includes computing in the host device a computed distance between the first and second storage systems, based at least in part on the responses, and comparing the computed distance to the threshold distance, and wherein the modifying of the asymmetric access state settings for the logical storage device is performed responsive to the computed distance being less than the threshold distance.
16. The computer program product of claim 15 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric logical unit access (ALUA) state settings for the logical storage device.
17. The computer program product of claim 15 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric namespace access (ANA) state settings for the logical storage device.
18. A method comprising:
identifying a logical storage device accessible in at least first and second storage systems;
measuring response times for accessing the logical storage device in each of the first and second storage systems; and
modifying, based at least in part on the measured response times, asymmetric access state settings for the logical storage device;
wherein measuring response times for accessing the logical storage device in each of the first and second storage systems comprises sending one or more commands from a host device to each of the first and second storage systems, receiving responses to each of the one or more commands in the host device from each of the first and second storage systems, comparing in the host device the responses received from the first and second storage systems, the responses including at least a first response received from the first storage system and a second response received from the second storage system, and identifying in the host device that the host device is configured as an equidistant host device relative to the first and second storage systems, based at least in part on a result of the comparing of the responses from the first and second storage systems, by the host device, indicating that the first and second storage systems are less than a threshold distance apart from one another, wherein the comparing of the responses includes computing in the host device a computed distance between the first and second storage systems, based at least in part on the responses, and comparing the computed distance to the threshold distance, and wherein the modifying of the asymmetric access state settings for the logical storage device is performed responsive to the computed distance being less than the threshold distance; and
wherein the method is performed by at least one processing device comprising a processor coupled to a memory.
19. The method of claim 18 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric logical unit access (ALUA) state settings for the logical storage device.
20. The method of claim 18 wherein modifying asymmetric access state settings for the logical storage device comprises modifying asymmetric namespace access (ANA) state settings for the logical storage device.