fmt(1m) manual page
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fmt - format a LUN of a C2425/7 disk array
fmt special
fmt formats one LUN of the C2425/7 disk array associated with
device special file special. The format will usually be a soft or zeroing
format, in which the controller writes zeroes to the data area and parity
area, if any, of the LUN.
- NOTE:
- The above should always be true of a sub-LUN,
but the controller may decide, based on certain conditions, to do a full
format of a regular LUN, which consists of sending a mode select and a
media initialization command to the physical drive(s) in question, followed
by zeroing the data and parity area, if any. The conditions which will
cause a full format to be done are as follows:
- 1. The controller received
a Mode Select command which requires a drive
- sector size change.
- 2. The
controller received a Mode Select command which changed a parameter
- in
the Format Device Page (0x03).
- 3. The LUN contains one or more failed drives.
In this case only a certain
- subset of the drives containing the failed
drives will be formatted.
- 4. Either the FmtData or the CmpLst bit in the
Format Unit CDB is set.
fmt returns the following value:
- 0
- Successful completion.
- -1
- Command failed.
Errors
can occur at many points in the execution of a given utility, caused by
bad user input, failed calls to the operating system and other situations.
These fall roughly into three categories: errors discovered by the utility
program, errors returned by system calls, and errors occurring at the
device or SCSI communication level.
The following messages are generated
by the utility itself:
- usage: fmt <special>
- An error in command syntax has occurred. Re-enter command
with all required arguments, in the order shown.
- fmt: LUN # too big
- The
LUN number, which is derived from the device special file name, is out
of range.
- fmt: Not a raw file
- Utilities must be able to open the device
file for raw access.
- fmt: LUN does not exist
- The addressed LUN is not configured,
and thus is not known to the array controller.
- fmt: Not a C2425/7 disk
array
- The device being addressed is not a C2425/7 disk array.
A second class
of errors consists of those associated with the device itself, or with
the communication over the SCSI channel. Sense data associated with the
failed operation will be printed out.
A third class of errors consists of
those occurring during system calls. The fmt utility makes the following
system calls:
- malloc(),
- free(), stat(), open(), close(), read(), write(),
and ioctl().
See the documentation for these HP-UX calls to obtain a list
of specific error conditions and their status. The utility itself does
not alter the value of errno, and the interpretation of the errno for
printing purposes is done by the system utility strerror().
To format
the C2425/7 disk array LUN /dev/rdsk/c410d5l2s0:
- fmt /dev/rdsk/c410d5l2s0
The fmt command will destroy all user data on the addressed LUN.
This utility is currently supported only on the Series 700
machines.
fmt was developed by HP.
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