On basic GUID partition table (GPT) disks, assigns the GPT attribute(s) to the partition with focus. Syntax: GPT ATTRIBUTES= ...

On basic GUID partition table (GPT) disks, assigns the GPT attribute(s) to     the partition with focus.  Syntax:  GPT ATTRIBUTES=      ATTRIBUTES=                  The hexadecimal value indicating the attributes to apply to the                 partition with focus. The GPT attribute field is a 64-bit field                 that contains two subfields. The higher field is interpreted                 only in the context of a particular partition type GUID, while                 the lower field is common to all partition types.                  All partitions have the following attribute:                  0x0000000000000001 marks the partition as required. This                 indicates to all disk management utilities that the partition                 should not be deleted. The EFI System partition contains only                 those binaries necessary to start the operating system. This                 makes it easy for OEM- or operating system-specific binaries to                 be placed in other partitions.                  For basic data partitions, the following attribute is defined:                  0x8000000000000000 prevents the partition from having a drive                 letter automatically assigned. By default, each partition is                 assigned a new drive letter. Setting this attribute ensures                 that when a disk is moved to a new computer, a new drive letter                 will not be automatically generated. Instead, the user can                 manually assign drive letters.                  Other attributes can be added at any time.      GPT partition attributes give additional information about the use of the     partition. Some attributes are specific to the partition type GUID.      A basic GPT partition must be selected for this operation to succeed.      Caution:          Changing the GPT attributes might cause your basic data volumes to be         unmountable or fail to be assigned drive letters. Unless you are an         original equipment manufacturer (OEM) or an IT professional experienced         with GPT disks, do not change GPT attributes.  Example:      GPT ATTRIBUTES=0x8000000000000000