Let say currently you have hdisk0 -hdisk8, and you want the new disks to start with number 10 instead of hdisk9.
You can create a dummy disk device with the name hdisk9:
# mkdev -l hdisk9 -p dummy -c disk -t hdisk -w 0000
Note that running the command above may result in an error. However, if you run the following command afterwards, you will notice that the dummy disk device indeed has been created:
# lsdev -Cc disk | grep -w hdisk9 hdisk9 Defined SSA Logical Disk Drive
Now run the cfgmgr command to discover the new disk. You’ll notice that the new disk will now be discovered as hdisk10.
You can choose to remove the dummy disk device.
# rmdev -dl hdisk1