PRIMECLUSTER Global Disk Services Configuration and AdministrationGuide 4.3

2.3.8 Disk Label

Disk label is an area at the front of each disk on which geometry and slice information are stored.

In RHEL, two types of disk labels below can be used:

• MSDOS label (Also called MBR label)

• GPT label

Information

Creation and change of the disk labels can be executed with the parted(8) command.

Disk label types of disks registered with a class are indicated as below:

For a root class [EFI]

It will be GPT type.

For local and shared classes

It varies according to the environment where 1 TB or larger disks are supported or not.

• For the environment where 1 TB or larger disks are unsupported

  It will be MSDOS type.

• For the environment where 1 TB or larger disks are supported [4.3A10 or later]

  It will be the same as the disk label type of a class.

  Disk label type of a class is determined by the size of the disk first registered with the class and the disk label type as below.

  Disk first registered with the class		Disk in the class
  Size	Disk label type before registered	Disk label type after registered (Disk label type of a class)
  Smaller than 2 TB	No label MSDOS type	MSDOS type
  	GPT type	GPT type
  2 TB or larger	No label MSDOS type GPT type

  
  Also, the size of a disk that can be registered with the class is determined by the disk label type of a class.

  • For MSDOS type: Smaller than 2 TB

  • For GPT type: Smaller than 2 TB or 2 TB or larger (both available)

  
  The disk label type of a class can be viewed in the LABEL field of Class information that is displayed with the sdxinfo -C -e label command.

  See

  For the environment where 1 TB or larger disks are supported, see "1 TB or larger disks [4.3A10 or later]" in "2.3.9 Disk Size."

  
  

Note

Local and shared classes of GPT label [4.3A10/4.3A20]

• In local and shared classes of GPT label, the functions below are unavailable:

  • Mirroring

  • Concatenation

  • Striping

  • Changing the physical slice attribute value of volume

  • GDS Snapshot

• When using the following function in local and shared classes of GPT label, a GDS patch is required:

  • sdxconfig command

    Version	OS	Package name	Patch number
    4.3A10	RHEL6(Intel64)	FJSVsdx-bas	T005774LP-11
    4.3A20	RHEL6(Intel64)	FJSVsdx-bas	T007868LP-05