radisk.8

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)radisk.8	3.1	11/24/87
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.\" ditroff \-Tln01 \-t \-man filename | lpr \-n \-Pln &
.TH radisk 8
.UC 4
.SH Name
radisk \- Digital Storage Architecture (DSA) disk maintenance
.SH Syntax
.B /etc/radisk
.sp
.B radisk
.B \-c 
.I LBN
.I length
.I special
.RE
.br
.B radisk
.B \-e
.I special
.br
.B radisk
.B \-n
.I special
.br
.B radisk
.B \-r
.I LBN
.I special
.br
.B radisk
.B \-s
.I LBN
.I length
.I special
.SH Description
.NXR "radisk utility"
.NXR "DSA disk" "managing"
.NXS "Digital Storage Architecture" "DSA disk"
The Digital Storage Architecture (DSA) disk maintenance program
.PN radisk
provides the essential functions to manage DSA 
disk devices. The
.PN radisk
command must be used on unmounted disk partitions to insure correct
results.
.PP
The 
.I LBN 
is a decimal number that represents the logical block number as
reported in the errorlog file.  The 
.I LBN 
is the actual disk block number
starting from the beginning of the disk. 
.PP
The
.I length 
is a decimal number that indicates how many (512 byte) blocks to
process.  The length specified may be 
.B \-1 
to indicate the last block of the specified partition.
.PP
The 
.I special 
file specified is used with 
.B \-c, \-e, \-n,  
and 
.B \-r 
options and indicates an unmounted 
.B c
partition of a character device special file.
.SH Options
The following options may be set with 
.PN radisk .
.NXR "radisk utility" "options"
.IP \fB\-c\fR 5  
Clears a forced error indicator on the range of specified LBNs.  The
forced error condition indicates that the data in the disk block is
bad.  The disk block is good, but the data can not be read without
getting an error detection code (EDC) error.  This option will cause the
forced error condition to be removed.  After the forced error indicator
is cleared, the EDC error will not be reported nor will the data be
marked as bad.  
.IP
All indications that the data is corrupt are lost.  The
data should be restored either by manual methods or with the 
.PN restore
command. The 
.PN radisk 
command affects the integrity of the data on a disk and should be
followed by a file system restore if data is affected.
.IP \fB\-e\fR 5
Sets the exclusive access attribute associated with the specified disk.  This
attribute is provided by multihost controllers to restrict access to a disk
to one host.  The 
.PN radisk 
command will return a failure status if the disk is already exclusively 
associated with another host or the underlying controller does not provide
multihost support.
If the 
command is issued to a disk that is currently mounted and the command fails,
the disk will no longer be online to this host.  For this reason the
\f(CW\-e\fR option should not be issued to a disk that is mounted.
.IP \f(B\-n\fR 5
Clears the exclusive access attribute associated with the specified disk.  
If the controller provides multihost support and the exclusive access attribute
is not set for a particular disk, it would be possible for the disk to be 
accessed by more than one host.
The 
.PN radisk 
command will return a failure status if the disk is not currently and exclusively
associated with this host or the underlying controller does not provide
multihost support.
.IP \fB\-r\fR 5
Replaces a block on the disk specified by LBN. See Restrictions.
.IP \fB\-s\fR 5
Starts a scan for bad blocks on the specified area on a disk. Bad blocks
are disk blocks that have data transfer errors to the extent that they
cannot be relied on.  When a bad block is found, it is replaced and the
bad block's LBN is reported.  The LBN specified with the
.PN \-s 
option can be 
.B 0 
to indicate the first block in the specified partition.  If 
.B 0
is specified, however, the program starts searching from the first block 
of the partition. The 
.PN \-s 
option will accept any valid partition on the disk. This allows any
partition to be scanned without scanning the entire disk and ensures
that the specified partition is free of bad blocks. As an example,
.PN /dev/rra3h 
indicates the 
.B h 
partition of the third logical disk unit.
.PP
.DT
.SH Diagnostics
The
.PN radisk
command generates messages when the user is not privileged, when the
LBN is not in the specified partition, and when the length exceeds the
size of the partition.
.SH Restrictions
You must be in single-user mode when using the
.PN \-c ,
.PN \-r ,
and
.PN \-s
options of the
.PN radisk
program.  If you are in multiuser mode, 
.PN radisk
hangs the system and cannot be killed.  If this happens, you must reboot.
.PP
The 
.PN \-r 
option is supported only with those DSA disks which use host-initiated
dynamic bad block replacement. 
.PP
The
.PN \-e
and
.PN \-n
options are only supported on controllers that provide multi-host support.
These options are only supported on HSC Version 5.00 or later.
.SH See Also
dkio(4), ra(4), sdc(4), chpt(8), mount(8), restore(8)
.br
.I "Guide to System Disk Maintenance"