HD(HW) UNIX System V
Name
hd - internal hard disk drive
Description
Block-buffered access to the primary hard disk is provided
through the following block special files: hd00, hd01
through hd04, hd0a and hd0d, root, and swap. Block-buffered
access to the secondary hard disk is provided through the
following block special files: hd10, hd11 through hd14,
hd1a.
hd00 refers to the entire physical disk; hd01 through hd04
refer to the fdisk partitions. root refers to the root file
system; swap refers to the swap area; The block special
files access the disks via the system's normal buffering
mechanism and may be read and written without regard to the
size of physical disk records.
Character special files follow the same naming convention as
the block special files except that the character special
file is prefaced with an ``r''. For example, the character
special file referring to the entire physical disk is
/dev/rhd00.
The following are the names of the fixed disk partitions.
Each partition can be accessed through a block interface,
for example /dev/hd01, or through a character (raw)
interface, for example /dev/rhd01.
The above devices follow the XENIX naming convention.
Equivalant UNIX devices are found in the /dev/dsk
(character) and /dev/rdsk (raw) directories. In the table
that follows, both XENIX UNIX devices are shown. XENIX
devices extend only to disks located on the first
controller; beyond this, the UNIX devices shown must be
used.
______________________________________________________________________
| Device File Names for Fixed Disks |
|___________________________________________________________________|
| | | |
| First Controller | Second Controller | |
| Disk 1 Disk 2 | Disk 1 Disk 2 | Partition |
|_____________________|___________________________|_________________|
|/dev/hd00 /dev/hd10 |/dev/dsk/4s0 /dev/dsk/5s0 | entire disk |
|/dev/rhd00 /dev/rhd10|/dev/rdsk/4s0 /dev/rdsk/5s0| |
|_____________________|___________________________|_________________|
|/dev/hd01 /dev/hd11 |/dev/dsk/4s1 /dev/dsk/5s1 | first partition |
|/dev/rhd01 /dev/rhd11|/dev/rdsk/4s1 /dev/rdsk/5s1| |
|_____________________|___________________________|_________________|
|/dev/hd02 /dev/hd12 |/dev/dsk/4s2 /dev/dsk/5s2 | second partition|
|/dev/rhd02 /dev/rhd12|/dev/rdsk/4s2 /dev/rdsk/5s2| |
|_____________________|___________________________|_________________|
|/dev/hd03 /dev/hd13 |/dev/dsk/4s3 /dev/dsk/5s3 | third partition|
|/dev/rhd03 /dev/rhd13|/dev/rdsk/4s3 /dev/rdsk/5s3| |
|_____________________|___________________________|_________________|
|/dev/hd04 /dev/hd14 |/dev/dsk/4s4 /dev/dsk/5s4 | fourth partition|
|/dev/rhd04 /dev/rhd14|/dev/rdsk/4s4 /dev/rdsk/5s4| |
|_____________________|___________________________|_________________|
|/dev/hd0a /dev/hd1a |/dev/dsk/4sa /dev/dsk/5sa | active partition|
|/dev/rhd0a /dev/rhd1a|/dev/rdsk/4sa /dev/rdsk/5sa| |
|_____________________|___________________________|_________________|
|/dev/hd0d /dev/hd1d |/dev/dsk/4sd /dev/dsk/5sd | DOS partition |
|/dev/rhd0d /dev/rhd1d|/dev/rdsk/4sd /dev/rdsk/5sd| |
|_____________________|___________________________|_________________|
|/dev/root | | root file system|
|/dev/rroot | | |
|_____________________|___________________________|_________________|
|/dev/swap | | swap area |
|/dev/rswap | | |
|_____________________|___________________________|_________________|
Note that the root and swap file exist only for the root
disk.
To access DOS partitions, specify letters such as ``C:'' or
``D:'' to indicate first or second partitions. The file
/etc/default/msdos contains lines that assign a letter
abbreviation for the DOS device name. Refer to dos(C).
The following table lists the minor device number
definitions for the hard disk special files, along with
examples. Note that the block and character special devices
share the same minor device definition. The minor device
number definition is as follows: bits 7 and 6 denote
physical drive, bits 5-3 denote virtual(fdisk) partition and
bits 2-0 denote divvy partition.
______________________________________________________________________
| Minor Device Bits |
|____________________________________________________________________|
|Phys. Virtual divvy Device special Description |
| 7 6 5 4 3 2 1 0 file name |
|____________________________________________________________________|
| |
| 0 0 0 0 0 0 0 0 /dev/hd00 whole PD 0 |
| 0 1 0 0 0 0 0 0 /dev/hd10 whole PD 1 |
| 1 0 0 0 0 0 0 0 /dev/dsk/4s0 whole PD 2 |
| 1 1 0 0 0 0 0 0 /dev/dsk/5s0 whole PD 3 |
| 0 0 0 0 1 1 1 1 /dev/hd01 PD 0, whole VD 1 |
| 0 0 0 1 0 1 1 1 /dev/hd02 PD 0, whole VD 2 |
| 0 0 0 1 1 1 1 1 /dev/hd03 PD 0, whole VD 3 |
| 0 0 1 0 0 1 1 1 /dev/hd04 PD 0, whole VD 4 |
| 0 0 1 0 1 1 1 1 /dev/hd0a PD 0, whole active VD |
| 0 0 1 1 0 1 1 1 /dev/hd0d PD 0, whole DOS VD |
| 0 0 1 0 1 0 0 0 /dev/root PD 0, active virtual, DP 0 |
| 0 0 1 0 1 0 0 1 /dev/swap PD 0, active virtual, DP 1 |
| 0 0 1 0 1 0 1 0 /dev/usr PD 0, active virtual, DP 2 |
| 0 0 1 0 1 1 1 0 /dev/recover PD 0, active virtual, DP 6 |
| 0 1 0 0 1 1 1 1 /dev/hd11 PD 1, whole VD 1 |
| 0 1 0 1 0 1 1 1 /dev/hd12 PD 1, whole VD 2 |
| 0 1 0 1 1 1 1 1 /dev/hd13 PD 1, whole VD 3 |
| 0 1 1 0 0 1 1 1 /dev/hd14 PD 1, whole VD 4 |
| 0 1 1 0 1 1 1 1 /dev/hd1a PD 1, whole active VD |
| 0 1 1 1 0 1 1 1 /dev/hd1d PD 1, whole DOS VD |
| 0 1 1 0 1 0 0 0 /dev/u0 PD 1, active virtual, DP 0† |
| 0 1 1 0 1 0 0 1 /dev/u1 PD 1, active virtual, DP 1† |
| 0 1 1 0 1 0 1 0 /dev/u2 PD 1, active virtual, DP 2† |
| 1 1 0 0 1 1 1 1 /dev/dsk/4s1 PD 2, whole VD 1 |
| 1 1 0 1 0 1 1 1 /dev/dsk/4s2 PD 2, whole VD 2 |
| 1 1 0 1 1 1 1 1 /dev/dsk/4s3 PD 2, whole VD 3 |
| 1 1 1 0 0 1 1 1 /dev/dsk/4s4 PD 2, whole VD 4 |
| 1 1 1 0 1 1 1 1 /dev/dsk/4sa PD 2, whole active VD |
| 1 1 1 1 0 1 1 1 /dev/dsk/4sd PD 2, whole DOS VD |
| 1 1 0 0 1 1 1 1 /dev/dsk/5s1 PD 3, whole VD 1 |
| 1 1 0 1 0 1 1 1 /dev/dsk/5s2 PD 3, whole VD 2 |
| 1 1 0 1 1 1 1 1 /dev/dsk/5s3 PD 3, whole VD 3 |
| 1 1 1 0 0 1 1 1 /dev/dsk/5s4 PD 3, whole VD 4 |
| 1 1 1 0 1 1 1 1 /dev/dsk/5sa PD 3, whole active VD |
| 1 1 1 1 0 1 1 1 /dev/dsk/5sd PD 3, whole DOS VD |
|____________________________________________________________________|
| | |
|KEY | VD = virtual drive PD = physical drive |
| | DP = divvy partition † = user-defined name |
| | |
|_____|_____________________________________________________________|
The device files usr and u[0-2] are optional filesystem
names; these nodes are not present unless created by the
system administrator.
Files
/dev/hd0a /dev/hd1a /dev/usr
/dev/rhd0a /dev/rhd1a /dev/rusr
/dev/hd0[0-4] /dev/hd1[0-4] /dev/root
/dev/rhd0[0-4] /dev/rhd1[0-4] /dev/rroot
/dev/hd0d /dev/hd1d /dev/swap
/dev/rhd0d /dev/rhd1d /dev/rswap
/dev/dsk/4s0 /dev/dsk/4s4 /dev/dsk/5s3
/dev/dsk/5s0 /dev/dsk/4sa /dev/dsk/5s4
/dev/dsk/4s1 /dev/dsk/4sd /dev/dsk/5sa
/dev/dsk/4s2 /dev/dsk/5s1 /dev/dsk/5sd
/dev/dsk/4s3 /dev/dsk/5s2
See Also
fdisk(ADM), badtrk(ADM), divvy(ADM), dos(C), mkdev(ADM)
Diagnostics
The following messages are among those that may be printed
on the console:
invalid fixed disk parameter table
and:
error on fixed disk (minor n), block = nnnnn,
cmd=nnnnn, status=nnnn,
Sector = nnnnn, Cylinder/head = nnnnn
Possible reasons for the first error include:
- The kernel is unable to get drive specifications, such as
number of heads, cylinders, and sectors per track, from
the disk controller ROM.
- Improper configuration.
- The disk is not turned on.
- The disk is not supported.
The second error specifies the following information:
- block : The UNIX block number within the device.
- cmd : The last command sent to the disk controller.
- status : The error status from the disk controller.
- Sector and Cylinder/head specify the location of a
possible flaw. This information is used with
badtrk(ADM).
Notes
On the first disk, hd00 denotes the entire disk and is used
to access the master boot block which includes the fdisk
partition table. For the second disk, hd10 denotes the
entire disk and is used to access its fdisk partition table.
Do not write to hd10 and hd00.
(printed 8/30/89) HD(HW)