cmdk(7D)							      Devices								  cmdk(7D)

NAME

       cmdk - common disk driver

SYNOPSIS

       cmdk@target, lun : [ partition | slice ]

DESCRIPTION

       The  cmdk  device  driver  is  a  common interface to various disk devices. The driver supports magnetic fixed disks and magnetic removable
       disks.

       The cmdk device driver supports three different disk labels: fdisk partition table, Solaris x86 VTOC and EFI/GPT.

       The block-files access the disk using the system's normal buffering mechanism and are read and written  without	regard	to  physical  disk
       records. There is also a "raw" interface that provides for direct transmission between the disk and the user's read or write buffer. A sin-
       gle read or write call usually results in one I/O operation; raw I/O is therefore considerably more efficient when many bytes are transmit-
       ted. The names of the block files are found in /dev/dsk. Raw file names are found in /dev/rdsk.

       I/O  requests  to the magnetic disk must have an offset and transfer length that is a multiple of 512 bytes or the driver returns an EINVAL
       error.

       Slice 0 is normally used for the root file system on a disk, slice 1 as a paging area (for example, swap), and slice 2 for backing  up  the
       entire fdisk partition for Solaris software. Other slices may be used for usr file systems or system reserved area.

       The fdisk partition 0 is to access the entire disk and is generally used by the fdisk(1M) program.

FILES

       /dev/dsk/cndn[s|p]n	 block device (IDE)

       /dev/rdsk/cndn[s|p]n	 raw device (IDE)

				 where:

				 cn    controller n.

				 dn    lun n (0-1).

				 sn    UNIX system slice n (0-15).

				 pn    fdisk partition (0-36).

       /kernel/drv/cmdk 	 32-bit kernel module.

       /kernel/drv/amd64/cmdk	 64-bit kernel module.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |x86			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       fdisk(1M), mount(1M), lseek(2), read(2), write(2), readdir(3C), scsi(4), vfstab(4), attributes(5), dkio(7I)

SunOS 5.11							    4 Nov 2008								  cmdk(7D)