You may experience incorrect drive volume size while changing RAID modes between RAID 5, RAID 0 and JBOD. The total capacity of the RAID volume in the CalDigit Drive Utility is correct but not in Apple’s Disk Utility.
After configuring a new RAID or JBOD set, you may find that the drive capacity or volume capacity as incorrect in Apple Disk Utility and are unable to partition a new RAID or JBOD volume to the correct capacity (for example: T4 15 TB in RAID 5 becomes 5TB in Disk Utility). In this case, you can use the command line utility: diskutil, to clean up the ghost file system information from the previous partition, then use OS X Disk Utility to re-partition the new volume. Please follow the steps below.
1. Go to Terminal.
2. Login as root user. You will need to enable root user first. See the steps here: Enabling and using the “root” user in OS X
3. List down all the hard disks and volumes: diskutil list Then find the right IDENTIFIER for your T4 or T3. For example, it can be “disk2”
4. Type in the command: sudo diskutil eraseDisk JHFS+ volume name /dev/diskX
4-1. Where “volume name” is the name of the new T4 RAID5 or JBOD volume name.
4-2. /dev/diskX , where X is the identifier number you have found from step 3.
5. Once completed, you can go back to Disk Utility and check out the total capacity and re-partition the volume.
Additional Information: Enabling and using the “root” user in OS X
