.TH dump "" "" Command
.II "backup files"
.II "file^backup"
.PC "File-system backup utility"
\fBdump [\fIoptions\fB] [\fIargument ...\fB]\fR
.PP
.HS
.SH Options:
.IC \fB0-9\fR
Set dump level (default, 9)
.IC \fBb\fR
Next argument is blocking factor (default, 20)
.IC \fBd\fR
Next argument is density in bpi (default, 1600)
.IC \fBf\fR
Next argument is output device name
.IC \fBs\fR
Next argument is tape length in feet (default, 2300)
.IC \fBS\fR
Next argument is floppy disk size in blocks
.IC \fBu\fR
Update \fB/etc/ddate\fR
.IC \fBv\fR
Verbose (display date and tape length)
.HE
.B dump
dumps either all or a portion of file system
.I argument
to magnetic tape or floppy disks.
File-system dumps are in a format that permits
you to restore all or some of the files to the original file system,
and to select files either by name or by i-number.
.PP
A file-system dump includes all files changed since the
.I "dump since"
date, plus each file's full path name (for the benefit of
.BR dumpdir ).
.PP
.I options
specifies both the dump-since date and the processing options.
It is made up of characters from the set
.BR 0123456789bdfsSuv ,
which have the following meanings.
.IP \fB0-9\fR 0.4i
The digit gives the level number of the dump.
The dump-since date is the most recent date in the dump-date file
.B /etc/ddate
that is (1) associated with this file system and (2) has a level number
less than the current dump level.
For example, if you request a level-3 dump, \fBdump\fR will back up all
files not backed up since the last level-2 dump.
A level-0 dump by definition backs up all files in the file system.
.IP \fBb\fR
The next
.I argument
gives the output tape's \fIblocking factor\|\fR.
The blocking factor is the number
of \fBdumpdata\fR structures in each tape block.
The default blocking factor is 20.
.IP \fBd\fR
The next
.I argument
gives the density of the output tape in bytes per inch.
The default density is 1600 bytes per inch (bpi).
.B dump
uses the density to compute the quantity of tape needed.
.IP \fBf\fR
The next
.I argument
gives the path name of the output file.
If no
.B f
option is given,
.B /dev/dump
is assumed.
.IP \fBs\fR
The next
.I argument
gives the length of the dump tape in feet.
.B dump
keeps a running total of the quantity of tape it has written, and it
asks for a new reel if it appears that the end of the reel is near.
The default length is 2,300 feet.
.IP \fBS\fR
The next
.I argument
gives the size of the dump output device, in blocks.
This is used only if you are backing up the file system to floppy disks
or streaming cartridge tape
rather than to nine-track magnetic tape.
.IP \fBu\fR
If the dump completes without error, update the
record of successful dumps kept in file
.BR /etc/ddate .
There is an entry in this file for every file system and every dump level.
.IP \fBv\fR
Inform the user of the \*(Qldump since\*(Qr date and
the length of tape used in feet.
The length is useful for computing the quantity of
tape remaining if multiple dumps are written onto a single reel of tape.
.PP
If no level number is given,
.B dump
assumes the
.I options
.BR 9u .
.SH Files
\fB/dev/dump\fR \(em Default dump device
.br
\fB/etc/ddate\fR \(em Dump date file
.SH "See Also"
.Xr "badscan," badscan
.Xr "commands," commands
.Xr "dumpdate," dumpdate
.Xr "dumpdir," dumpdir
.Xr "restor" restor
.SH Diagnostics
Most errors are fatal caused by a table overflowing, or a read or
write error on the input or output device.
.PP
.B dump
requires that its output be written to disks that are free of bad sectors.
If you write a dump to a disk with bad sectors, you will not be able to
restore files from that disk.
.PP
When formatting disks to be used with \fBdump\fR, use the command
.DM
	/etc/fdformat -v \fIdevice\fR
.DE
.PP
This forces
.B fdformat
to verify the format.
It takes twice as long, but it ensures that the disk is good at least at
a first level of testing.
Reject any disks that have any defects \(em or save them for use with
\*(CO file systems, which can map out bad sectors.
.SH Notes
Please note that
.B dump
is now regarded as being obsolete.
We strongly encourage users to use
.B cpio
instead.
