Once you add drives to the array and the data is striped across the drives, you are not able to remove a drive and shrink the disk group. The only way to get to a smaller size would be to back up the array and wipe the MD3000 and do a reconfigure with the amount of drives you want to be in the system. Please feel free to let me know if you have any further questions.
(I am new to Dell Storage). I have an MD 3000 where I created a disk group with 5 Physical Disks in RAID5 configuration. I can add new disk to add capacity but cannot figure out how do i remove a disk to reduce capacity. I cannot find any reference on Dell's site on these How To type of things. Any help will be appreciated.
How to remove a physical disk from disk group