HD(4)               Linux Programmer's Manual               HD(4)

NAME
       hd - MFM/IDE hard disk devices

DESCRIPTION
       Hd*  are  block devices to access MFM/IDE hard disk drives
       in raw mode.  The master drive on  the  primary  IDE  con-
       troller (major device number 3) is hda; the slave drive is
       hdb.  The master drive of  the  second  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 partition on that physical drive.
       The first form, hdX, is used to address the  whole  drive.
       Partition numbers are assigned in the order the partitions
       are discovered, and only  non-empty,  non-extended  parti-
       tions  get  a  number.  However, partition numbers 1-4 are
       given to the four partitions 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-diskla-
       bel partitioning 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 system; and /dev/hdb3 refers to the third DOS `pri-
       mary' 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
       mknod(1), chown(1), mount(8), sd(4)

Linux                    17 December 1992                       1