dasdfmt - formatting of DASD (ECKD) disk drives.
dasdfmt [-h] [-t] [-v] [-y] [-p] [-P] [-m step]
[-r cylinder] [-b blksize] [-l volser] [-d
layout]
[-L] [-V] [-F] [-k] [-C] [-M mode] device
dasdfmt formats a DASD (ECKD) disk drive to prepare it for
usage with Linux for S/390. The device is the node of the device
(e.g. '/dev/dasda'). Any device node created by udev for kernel 2.6 can be
used (e.g. '/dev/dasd/0.0.b100/disc').
WARNING: Careless usage of dasdfmt can result in
LOSS OF DATA.
- -h or --help
- Print usage and exit.
- -t or --test
- Disables any modification of the disk drive.
dasdfmt just prints out, what it would do.
- -v
- Increases verbosity.
- -y
- Start formatting without further user-confirmation.
- --norecordzero
- Remove permission for subsystem to format write record zero.
This is an expert option: Per default in recent dasd drivers, subsystems are
granted the permission to format write record zero. This option is used to
remove this permission.
- -L or
--no_label
- Omit the writing of a disk label after formatting.
This makes only sense for the 'ldl' disk layout.
The '-L' option has to be specified after the '-d ldl' option.
e.g. dasdfmt -d ldl -L /dev/...
- -V or
--version
- Print version number and exit.
- -F or --force
- Formats the device without performing sanity checking.
- -C or
--check_host_count
- Force dasdfmt to check the host access open count to ensure the device is
not online on another operating system instance
- -d layout or
--disk_layout=layout
- Formats the device with compatible disk layout or linux disk layout.
layout is either cdl for the compatible disk layout
(default) or ldl for the linux disk layout.
Compatible disk layout means a special handling of the first two tracks of
the volume. This enables other S/390 or zSeries operating systems to
access this device (e.g. for backup purposes).
- -p or
--progressbar
- Print a progress bar while formatting. Do not use this option if you are
using a 3270 console, running in background or redirecting the output to a
file.
- -P or
--percentage
- Print one line for each formatted cylinder showing the number of the
cylinder and percentage of formatting process. Intended to be used by
higher level interfaces.
- -m step or
--hashmarks=step
- Print a hashmark every step cylinders. The value step has to
be within range [1,1000], otherwise it will be set to the default, which
is 10.
You can use this option to see the progress of formatting in case you are
not able to use the progress bar option -p, e.g. with a 3270 terminal.
The value will be at least as big as the -r or --requestsize value.
- -M mode or
--mode=mode
- Specify the mode to be used to format the device. Valid modes
are:
- full
- Format the entire disk with the specified blocksize. (default)
- quick
- Format the first two tracks and write label and partition information.
Only use this option if you are sure that the target DASD already contains
a regular format with the specified blocksize. A blocksize can optionally
be specified using -b (--blocksize).
- expand
- Format all unformatted tracks at the end of the target DASD. This mode
assumes that tracks at the beginning of the DASD volume have already been
correctly formatted, while a consecutive set of tracks at the end are
unformatted. You can use this mode to make added space available for Linux
use after dynamically increasing the size of a DASD volume. A blocksize
can optionally be specified using -b (--blocksize).
- --check
- Perform a complete format check on a DASD volume. A blocksize can be
specified with -b (--blocksize).
- -r cylindercount or
--requestsize=cylindercount
- Number of cylinders to be processed in one formatting step. The value must
be an integer in the range 1 - 255.
Use this parameter to exploit any available PAV devices. The number of
cylinders optimally matches the number of associated devices, counting the
base device and all alias devices.
- -b blksize or
--blocksize=blksize
- Specify blocksize to be used. blksize must be a positive integer
and always be a power of two. The recommended blocksize is 4096 bytes.
- -l volser or
--label=volser
- Specify the volume serial number or volume identifier to be written to
disk after formatting. If no label is specified, a sensible default is
used. volser is interpreted as ASCII string and is automatically
converted to uppercase and then to EBCDIC.
e.g. -l LNX001 or --label=DASD01
The volser identifies by serial number the volume. A
volume serial number is 1 through 6 alphanumeric or one of the following
special characters: $, #, @, %. Enclose a serial number that contains
special characters in apostrophes. If the number is shorter than six
characters, it is padded with trailing blanks.
Do not code a volume serial number as SCRTCH, PRIVAT, or
Lnnnnn (L with five numbers); these are used in OS/390 messages to ask
the operator to mount a volume. Do not code a volume serial number as
MIGRAT, which is used by the OS/390 Hierarchical Storage Manager
DFSMShsm for migrated data sets.
NOTE: Try to avoid using special characters in the volume
serial. This may cause problems accessing a disk by volser.
In case you really have to use special characters, make sure you are using
quotes. In addition there is a special handling for the '$' sign. Please
specify it using '\$' if necessary.
e.g. -l 'a@b\$c#' to get A@B$C#
- -k or
--keep_volser
- Keeps the Volume Serial Number, when writing the Volume Label. This is
useful, if the Serial Number has been written with a VM Tool and should
not be overwritten.