Hello,
You have disk groups that are striped across enclosures. When you power down the enclosure you remove drives from the array. This simulates drive(s) removal.
The array controller stamps each drive with metadata that identifies the drive as belonging to a disk-group, vdisk, pool, etc and adds a time stamp. That time stamp is updated frequently. When you remove an enclosure the remaining drives in a disk-group/vdisk are updated but the removed drives do not get the time stamp update. So when you re-add the enclosure the drives in the enclosure have a time stamp that does not match the existing drives in the disk-group/vdisk. By design the array firmware will mark those drives as belonging to a disk-group/vdisk but in a leftover state if the time stamps are not coherant enough to automatically add back into the original disk-group/vdisk. At this point it is up to the user to take corrective steps.
You can use the Trust command to accept disks back into a disk-group/vdisk. Linear vdisks behave differently than virtual. You should use great caution when using Trust as this can lead to data integrity issues. Please read the MSA Troubleshooting Guide for further instructions and cautions when using Trust: https://support.hpe.com/hpsc/doc/public/display?docId=c05177410
Cheers,
Shawn
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