Why does an iSCSI LUN still show the same capacity on my Mac after I’ve increased its capacity on my NAS?
Applicable products:
- Devices running macOS 10.13 or later, iSCSI & Fibre Channel
Starting from version 10.13, macOS changed their file system to APFS. In APFS, iSCSI LUNs are treated as disks and disk information is recorded in an APFS container only during disk formatting. This means that after you add an iSCSI LUN from your NAS as a disk to your Mac, if you later increase the LUN capacity using iSCSI & Fibre Channel on your NAS, the new LUN capacity will not be updated in the APFS container records on your macOS device.
One way to work around this issue is to use Disk Utility on macOS to erase and then reformat the iSCSI LUN, so that macOS records the new LUN capacity. However, make sure to back up the LUN data first because all existing data on the LUN will be deleted during the process.