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HD(4) Linux Programmer's 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 is 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 nonempty, nonextended 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*