2V0-621 · Question #74
Refer to the Exhibit. An administrator is configuring a storage device as shown in the Exhibit. What is the expected effect on the stated device after running the command?
The correct answer is B. I/O will rotate on all storage targets that are Active Optimized state only. When Round Robin PSP is configured on an ALUA-capable storage device, VMware NMP restricts I/O rotation to paths in the Active Optimized state by default.
Question
Refer to the Exhibit. An administrator is configuring a storage device as shown in the Exhibit. What is the expected effect on the stated device after running the command?
Options
- AI/O will rotate on all storage targets regardless of port group state.
- BI/O will rotate on all storage targets that are Active Optimized state only.
- CI/O will rotate on all storage targets that are Active Unoptimized state only.
- DI/O will rotate on all storage targets that are on Available Nodes only.
How the community answered
(47 responses)- A17% (8)
- B66% (31)
- C4% (2)
- D13% (6)
Why each option
When Round Robin PSP is configured on an ALUA-capable storage device, VMware NMP restricts I/O rotation to paths in the Active Optimized state by default.
Round Robin PSP does not ignore port group or ALUA path states; it respects ALUA designations and will not blindly rotate across all targets regardless of their optimization state.
On ALUA-capable arrays, Active Optimized paths provide direct access through the storage controller that owns the LUN, delivering the best performance. The VMware NMP Round Robin PSP respects ALUA path states and by default only cycles I/O across Active Optimized paths, avoiding the higher latency of paths through non-owning controllers.
Active Unoptimized paths route I/O through a non-owning controller at higher latency and are used only as a fallback when no Active Optimized paths remain; Round Robin does not prefer or target them.
Available Nodes is not a recognized VMware ALUA path state; VMware NMP uses the states Active Optimized, Active Unoptimized, Standby, and Unavailable.
Concept tested: Round Robin PSP behavior on ALUA storage arrays
Source: https://docs.vmware.com/en/VMware-vSphere/6.0/com.vmware.vsphere.storage.doc/GUID-2F4D2BDA-3B8D-42D8-AB14-46B78B1D3E04.html
Topics
Community Discussion
No community discussion yet for this question.