mediainit(1)						      General Commands Manual						      mediainit(1)

NAME

       mediainit - initialize disk or partition DDS tape

SYNOPSIS

       fmt_optn] interleave] size] pathname

       scrub_character] scrub_count] special_file

DESCRIPTION

       initializes  mass  storage  media  by  formatting  the media, writing and reading test patterns to verify media integrity, then sparing any
       defective blocks found.	This process prepares the disk or tape for error-free operation.  Initialization destroys all existing	user  data
       in the area being initialized.

       can also be used for partitioning DDS tape media.  See the option below for further details.

       can also be used for disk scrubbing.  Disk scrubbing is the process of overwriting the entire disk with a single character.  See the option
       below for further details.

   Options
       The following command options are recognized.  They can be specified in any order, but all must precede the pathname or special_file.

       Options without parameters can be listed individually or grouped together.  Options with parameters must be listed individually, but  white
       space between the option and its parameter is discretionary.

	      Normally, 	  provides only fatal error messages which are directed to standard error.  The (verbose) option sends device-spe-
				  cific information related to low-level operation of to standard output (stdout).  This option is most useful	to
				  trained service personnel because it usually requires detailed knowledge of device operation before the informa-
				  tion can be interpreted correctly.

	      (re-certify)	  This option forces a complete tape certification whether or not the tape has	been  certified  previously.   All
				  record  of  any  previously  spared  blocks  is discarded, so any bad blocks will have to be rediscovered.  This
				  option should be used only if:

				  o  It is suspected that numerous blocks on the tape have been spared which should not have been, or

				  o  It is necessary to destroy (overwrite) all previous data on the tape.

	      The format option is a device-specific number in the range
				  through It is intended solely for use with certain SS/80 devices that support multiple media	formats  (indepen-
				  dent	from  interleave  factor).  For example, certain microfloppy drives support 256-, 512-, and 1024-byte sec-
				  tors.  passes any supplied format option directly through to the device.  The device	then  either  accepts  the
				  format  option  if it is supported, or rejects it if it is not supported.  Refer to device operating manuals for
				  additional information.  The default format option is

	      The interleave factor,
				  interleave, refers to the relationship between sequential logical records and sequential physical  records.	It
				  defines  the	number of physical records on the media that lie between the beginning points of two consecutively
				  numbered logical records.  The choice of interleave factor can have a substantial impact on disk performance.

	      Partition 	  DDS cartridge media into two logical separate volumes: partition 0 and partition 1:

				  o  size specifies the minimum size of partition 1 (in megabytes).  The maximum allowed value is 1200 megabytes.

				  o  Partition 0 is the remainder of the tape (partition 0 physically follows partition 1 on the tape).

				  The actual size of partition 1 is somewhat larger than the requested size to allow for tape media errors  during
				  writing.   Thus,  a  size  of  400 megabytes formats the DDS tape into two partitions where partition 1 holds at
				  least 400 megabytes of data, and the remainder of the tape is used for partition 0 (for  a  1300  megabytes  DDS
				  cartridge, this means that partition 0 has a size somewhat less than 900 megabytes).

				  Note	that  it is unnecessary to format a DDS tape before use unless the tape is being partitioned.  Unformatted
				  DDS media does not require initialization when used as a single partition tape.  Accessing partition 1 on a sin-
				  gle-partition tape produces an error.  To change a two-partition tape to single-partition, use with specified as
				  the size.

	      pathname		  pathname is the path name to the character (raw) device special file associated with the device unit	or  volume
				  that is to be initialized.  aborts if you lack either read or write permission to the device special file, or if
				  the device is currently open for any other process.  This prevents accidental initialization of the root  device
				  or any mounted volume.  locks the unit or volume being initialized so that no other processes can access it.

				  Except  for SCSI devices, pathname must be a device special file whose minor number of the device being initial-
				  ized has the diagnostic bit set.  For device special files with the diagnostic bit set, the  section	number	is
				  meaningless.	The entire device is accessed.

	      The		  scrub_character refers to the character input by the user.  The disk will be scrubbed using this character.  Any
				  character between or or can be specified.  The option must be used with the option.

	      If the		  option is specified, the disk will be scrubbed for scrub_count number of times.  This option must be	used  with
				  the option.

	      This option is used for disk scrubbing.
				  The  and  options  must be used with the option.  If both and options are not specified, then the device will be
				  scrubbed three times.

	      special_file	  The special_file is path name of the character (raw) device special file associated with the device that  is	to
				  be  scrubbed.   aborts  if you do not have either read or write permission to the device special file, or if the
				  device is currently open for any other process.  locks the device special file being scrubbed so that  no  other
				  processes can access it.

				  Note that before a device special file is scrubbed, if any file system is on the disk, you must unmount the file
				  system.

	      This option is used to verify the scrubbed disk.
				  The option randomly validates the scrubbed data written during the last pass of the  disk  scrub  process.   The
				  option must be used with the option.

       When  a	given  unit  contains  multiple volumes as defined by the drive controller, any available unit or volume associated with that con-
       troller can be initialized, independent of other units and volumes that share the same controller.  Thus, you can initialize  one  unit	or
       volume  to  any	format	or  interleave factor without affecting formats or data on companion units or volumes.	However, be aware that the
       entire unit or volume (as defined by the drive controller) is initialized without considering the possibility that  it  may  be	subdivided
       into smaller structures by the the operating software.  When such structures exist, unexpected loss of data is possible.

       dominates  controller  resources  and limits access by competing processes to other units or volumes sharing the same controller.  If other
       simultaneous processes need access to the same controller, some access degradation can be expected until initialization is complete;  espe-
       cially if you are initializing a tape cartridge in a drive that shares the root disk controller.

       In  general,  attempts  to carefully check any (format option) or (interleave options) supplied, and aborts if an option is out of range or
       inappropriate for the media being initialized.  Specifying an interleave factor or format option value of has the same effect as not speci-
       fying the option at all.

       For  disks  that  support interleave factors, the acceptable range is usually (no interleave) through n-1, where n is the number of sectors
       per track.  Refer to the appropriate device operating manual for recommended values.

       If a disk being initialized requires an interleave factor but none is specified, provides an appropriate, though  not  necessarily  optimum
       default.

       When  a	given device supports format options, the allowable range of interleave factors may be related to the specified format option.	In
       such instances, cannot check the interleave factor if one is specified.

   Notes
       Most types of mass storage media must be initialized before they can be used.  HP hard disks, flexible disks, and cartridge  tapes  require
       some form of initialization, but 9-track tapes do not.  Initialization usually involves formatting the media, writing and reading test pat-
       terns, then sparing any defective blocks.  Depending upon the media and device type, none, some, or all of the initialization  process  may
       have been performed at the factory.  completes whatever steps are appropriate to prepare the media for error-free operation.

       Most HP hard disks are formatted and exhaustively tested at the factory by use of a process more thorough but also more time-consuming than
       appropriate for However, is still valuable for ensuring the integrity of the media after factory  shipment,  formatting	with  the  correct
       interleave factor, and sparing any blocks which may have become defective since original factory testing was performed.

       HP  flexible  disks  are not usually formatted prior to shipment, so they must undergo the entire initialization process before they can be
       used.

       When a tape is certified, it is thoroughly tested and defective blocks are spared.  usually certifies a tape only if it has not been certi-
       fied  previously.   If  the  tape has been previously certified and spared, usually reorganizes the tape's spare block table, retaining any
       previous spares, and optimizing their assignment for maximum performance under sequential access.  Reorganizing the spare block table takes
       only a few seconds, whereas complete certification takes about a half-hour for 150-foot tapes, and over an hour for 600-foot tapes.

       Reorganization  of  a  tape's  spare  block table technically renders any existing data undefined, but the data is not usually destroyed by
       overwriting.  To ensure that old tape data is destroyed, which is useful for security, complete tape re-certification can  be  forced  with
       the option.

       Some  applications may require that a file system be placed on the media before use.  does not create a file system; it only prepares media
       for writing and reading.  If such a file system is required, other utilities such as or must  be  invoked  after  running  (see	newfs(1M),
       lifinit(1), and mkfs(1M)).

RETURN VALUE

       returns one of the following values:

	      0    Successful completion.
	      1    A device-related error occurred.
	      2    A syntax-related error was encountered.

ERRORS

       Appropriate error messages are printed on standard error during execution of

EXAMPLES

       Scrub the specified device special file using the default of three times (the default).

       Scrub the specified device special file twice with a scrub character of 0.

       Scrub the specified device special file twice with a scrub character of 0 and verify.

WARNINGS

       For  a  device  that  contains  multiple  units on a single controller, each unit can be initialized independently from any other unit.	It
       should be noted, however, that requires that there be no other processes accessing the device before initialization begins,  regardless	of
       which unit is being initialized.  If there are accesses currently in progress, aborts.

       Aborting  is  likely to leave the medium in a corrupt state, even if it was previously initialized.  To recover, the initialization must be
       restarted.

       During the initialization process, rejects all other accesses to the device being initialized, producing the error (see open(2)).

DEPENDENCIES

   Series 800
       Partitioning of DDS tape media option) is not supported.

AUTHOR

       was developed by HP.

SEE ALSO

       lifinit(1), mkfs(1M), newfs(1M), open(2).

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