rdump.8c

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)rdump.8c	2.4	8/20/87
.TH rdump 8c
.SH Name
rdump \- file system dump across the network
.SH Syntax
.B /etc/rdump
[ \-key [
.I argument
\&... ] \fIfilesystem\fP ]
.SH Description
.NXR "rdump command"
.NXA "rdump command" "rmt program"
.NXA "dump command" "rdump command"
.NXR "file system" "copying across network"
.NXM "rdump command" 
The
.PN rdump
command
copies to magnetic tapes, disks, or a dump image file all files
changed after a certain date
in the
.I filesystem.
The command is identical in operation to
.MS dump 8
except the 
.B f
key must be specified and the file
supplied should be of the following form:
.PP
.I remote-system-name:device-or-file
.PP
The
.PN rdump
command
initiates a remote server,
.PN /etc/rmt ,
on the remote system to access the remote
device or file.
.SH Options 
With the
.PN dump
command, you specify a string of one or more of the
options described below.  If no options 
are specified, the key
.B 9u
is assumed.
.TP 8 
.B  0\-9
This number is the ``dump level.''
All files that were modified 
since the last date stored
in the file
.PN /etc/dumpdates
for the filesystem at lesser levels will be dumped.
If no date is determined by the level,
the beginning of time is assumed.
Thus, the level 
.B 0
causes the entire filesystem to be dumped, a level 5 is used
for a weekly backup and a level 9 for a daily backup.
.TP 8
.B B
The next
.I argument
is a number that specifies the size, in 1024-byte blocks,
of a storage medium, such as a diskette or a removable disk.
See the first example.
.TP 8
.B d
The density of the tape, expressed in bits per inch, is taken
from the next
.I argument.
This density is used in calculating the amount of tape
used per reel.  The default density is 1600 bpi.
.TP 8 
.B f
Place the dump on the file or device specified by the next
.I argument.
This file is specified as remote-system-name:device-or-file.
.TP 8
.B n
Notify, by means similar to a
.MS wall 1
command,
all users in the group ``operator'' when
.PN dump
needs operator attention.
.TP 8
.B o
Provides compatibility with non-ULTRIX or pre-ULTRIX Version 2.0 
remote systems.
.TP 8
.B S
Displays amount of space used by 
.PN dump
without performing the dump operation.  This is used
for presizing either for file preallocation or to ensure
the correct number of tapes or disks are on hand.
.TP 8
.B s
The next
.I argument
specifies the size of the dump tape (in feet).  When
the specified size is reached,
.PN dump
waits for the reel to be changed.  The default tape size
is 2300 feet.
.TP 8 
.B u
If the dump completes successfully,
writes the date of the beginning of the dump to
file
.PN /etc/dumpdates .
This file records a separate date for
each filesystem and each dump level.
The format of
.PN /etc/dumpdates
consists of one
free format record per line:
filesystem name, increment level
and
.MS ctime 3
format dump date.  
The superuser can carefully edit
.PN /etc/dumpdates
to change any of the fields.
.TP 8 
.B W
The
.PN dump
utility tells the operator what file systems need to be dumped.
This information is taken from the files
.PN /etc/dumpdates
and
.PN /etc/fstab .
The
.PN W
option causes
.PN dump
to print out, for each file system in
.PN /etc/dumpdates ,
the most recent dump date and level,
and highlights those file systems that should be dumped.
If the 
.PN W
option is used, all other options are ignored, and
.PN dump
exits immediately.
.TP 8 
.B w
Unlike 
.PN W , 
.PN w 
lists only those filesystems that need to be dumped.
.SH Examples
This example reports number of bytes to be output for a
level 0 dump of the root file system.  Please note: the file
.PN test 
is not created.
.EX
rdump OSf system:test /
.EE
This example dumps the root(/) file system from the local
system to a remote system named ``nihil''.  A level 0
dump to tape is performed and the 
.PN /etc/dumpdates 
file is updated.
.EX
rdump 0uf nihil:/dev/rmt0h /
.EE
.PP
This example dumps the user (/usr) file system from the local
system to a remote system named ``dickens'' using the RX50
device named 
.PN /dev/rra1a 
for output.  A level 0 dump is
performed, but the 
.PN /etc/dumpdates
file is not updated.
.EX
rdump 0f dickens:/dev/rra1a /usr
.EE
.PP
This example dumps the root file system to a non-ULTRIX or ULTRIX before
Version 2.0 remote system.  A level 0 dump to a tape drive is performed
and the
.PN /etc/dumpdates
file is updated.  
.EX
rdump 0ouf system:/dev/rmt0h /
.EE
.PP
This example dumps the root file system to a non-ULTRIX or ULTRIX before
Version 2.0 remote system.  A level 0 dump to the rx50 device is performed
and the
.PN /etc/dumpdates 
file is updated.
Note the specification of 400 as the device size in 1,024 byte blocks.
.EX
rdump 0ouBf 400 system:/dev/rra1a /
.EE
.PP
If you want to use / and 
.PN /usr ,
you must have these entries
in the 
.PN /etc/fstab 
file.
.SH Diagnostics
Same as 
.MS dump 8
with a few extra related to the network.
.SH Files
.TP 15
.PN /dev/tt
Required for user interface
.SH See Also
dump(8),
rmt(8c)