Mac OS X: Command Line Disk Management

Now that you are looking at a command prompt on the target server use the diskutil command to prepare the hard drives for installation.  As with the Disk Utility application, double (nay, triple) check your drives to make sure that either they are backed up or you absolutely positively do not need any of the data they contain, or you will not ever likely see your data again (my precious).  When you run diskutil list you will see a listing of all partitions on your disk as can be seen below:

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *149.1 Gi   disk0

   1:                        EFI                         200.0 Mi   disk0s1

   2:                  Apple_HFS Leopard                 75.0 Gi    disk0s2

   3:                  Apple_HFS LeopardServer           15.0 Gi    disk0s3

   4:                  Apple_HFS Tiger                   58.5 Gi    disk0s4

As you will likely want to create a RAID for the boot volume of your server you will likely use the createRAID verb followed by a  flag indicating the type of RAID to create.  Available raid types from the command line include mirror, stripe and concat which result in RAID 1, RAID 0 and JBOD respectively.  Following the RAID type you will provide a name for your RAID by using the setName verb followed by the name of the disk.  Next you will include the file system type to put the RAID on.  Available file systems in Mac OS X Server include “Journaled HFS+”, “HFS+”, Case-sensitive HFS+”, Case-sensitive Journaled HFS+”, HFS”, MS-DOS FAT16″, “MS-DOS FAT32″, MS-DOS FAT12″, “MS-DOS”, “UDF”, “UFS” and “ZFS”.  Most administrators are going to choose “JHFS+”, which is an available shortened version of Journaled HFS+.  The final aspect of the command that will build your RAID is the disks that will be included in the RAID set.  Each disk was identified in the #: column from the list command previously run.  So simply list then as disk2, disk3 or whichever disks you are looking to add to the RAID.  

 

To use this in an example, we will build a mirror of disk2 and disk3 from our above list.  The name of the RAID will be ServerRAID and the file system will be Journaled HFS +.  The resultant command would end up being:

diskutil createRAID mirror ServerRAID JHFS+ disk2 disk3

Note: do not mess with the GUID_partiton_scheme or the EFI partition; doing so (unless you know exactly what you are doing) will likely result in a very sad system administrator.

Comments are closed.