Restoring the Optimal Path for Logical Drives on IBM DS Storage
After a controller or link failure, logical drives on IBM DS5000 may still be accessed via non-preferred controllers. Once the fault is resolved, you can reassign the logical drives to their preferred paths using Storage Manager. The following screenshots are from the official IBM DS5000 manual; the interface shown is Storage Manager 10. For other versions, verify the corresponding menu names in the relevant manuals.
Pre-recovery checks
First, confirm that controllers, host links, and multipathing have returned to normal operation. If the root cause has not been eliminated, logical drives may switch back to non-preferred paths; do not use repeated reassignments as a substitute for troubleshooting.
Recovery in Storage Manager
- Open the Subsystem Management window.
- Select Advanced → Recovery → Redistribute Logical Drives.
- Wait for the reassignment to complete, then check the progress and final status.
Post-recovery verification
The storage should return to Optimal status, and confirm that the paths are available from the host side. Reassigning a large number of LUNs may take considerable time; if non-preferred paths are still reported, continue checking the original fault and the host multipathing configuration.