HD(4)			   Linux Programmers Manual			HD(4)



NAME
       hd - MFM/IDE hard disk devices

DESCRIPTION
       The hd* devices are block devices to access MFM/IDE hard disk drives in
       raw mode.  The master drive on the primary IDE controller (major device
       number 3) is hda; the slave drive is hdb.  The master drive of the sec
       ond controller (major device number 22) is hdc and the slave hdd.

       General IDE block device names have the form hdX, or hdXP, where X is a
       letter denoting the physical drive, and P is a number denoting the par
       tition on that physical drive.  The first form, hdX, is used to address
       the  whole drive.  Partition numbers are assigned in the order the par
       titions are discovered, and only non-empty, non-extended partitions get
       a  number.  However, partition numbers 1-4 are given to the four parti
       tions described in the MBR (the "primary"  partitions),	regardless  of
       whether they are unused or extended.  Thus, the first logical partition
       will be hdX5.  Both DOS-type partitioning and BSD-disklabel  partition
       ing  are supported.  You can have at most 63 partitions on an IDE disk.

       For example, /dev/hda refers to all of the first IDE drive in the  sys
       tem;  and  /dev/hdb3 refers to the third DOS "primary" partition on the
       second one.

       They are typically created by:

	      mknod -m 660 /dev/hda b 3 0
	      mknod -m 660 /dev/hda1 b 3 1
	      mknod -m 660 /dev/hda2 b 3 2
	      ...
	      mknod -m 660 /dev/hda8 b 3 8
	      mknod -m 660 /dev/hdb b 3 64
	      mknod -m 660 /dev/hdb1 b 3 65
	      mknod -m 660 /dev/hdb2 b 3 66
	      ...
	      mknod -m 660 /dev/hdb8 b 3 72
	      chown root:disk /dev/hd*

FILES
       /dev/hd*

SEE ALSO
       chown(1), mknod(1), sd(4), mount(8)

COLOPHON
       This page is part of release 3.05 of the Linux  man-pages  project.   A
       description  of	the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



Linux				  1992-12-17				 HD(4)