NAME
dump - incremental file system dump
SYNOPSIS
dump [ key [ arguments ] filesystem ]
DESCRIPTION
Dump makes an incremental file system dump on magtape of all
files changed after a certain date. The key argument speci-
fies the date and other options about the dump. Key con-
sists of characters from the set abcfiu0hds.
a Normally files larger than 1000 blocks are not incre-
mentally dump; this flag forces them to be dumped.
b The next argument is taken to be the maximum size of
the dump tape in blocks (see s).
c If the tape overflows, increment the last character of
its name and continue on that drive. (Normally it asks
you to change tapes.)
f Place the dump on the next argument file instead of the
tape.
i the dump date is taken from the entry in the file
/etc/dtab corresponding to the last time this file sys-
tem was dumped with the -u option.
u the date just prior to this dump is written on
/etc/dtab upon successful completion of this dump.
This file contains a date for every file system dumped
with this option.
0 the dump date is taken as the epoch (beginning of
time). Thus this option causes an entire file system
dump to be taken.
h the dump date is some number of hours before the cur-
rent date. The number of hours is taken from the next
argument in arguments.
d the dump date is some number of days before the current
date. The number of days is taken from the next argu-
ment in arguments.
s the size of the dump tape is specified in feet. The
number of feet is taken from the next argument in argu-
ments. It is assumed that there are 9 standard UNIX
records per foot. When the specified size is reached,
the dump will wait for reels to be changed. The
default size is 2200 feet.
1
If no arguments are given, the key is assumed to be i and
the file system is assumed to be /dev/rp0.
Full dumps should be taken on quiet file systems as follows:
dump 0u /dev/rp0
ncheck /dev/rp0
The ncheck will come in handy in case it is necessary to
restore individual files from this dump. Incremental dumps
should then be taken when desired by:
dump
When the incremental dumps get cumbersome, a new complete
dump should be taken. In this way, a restore requires load-
ing of the complete dump tape and only the latest incremen-
tal tape.
DIAGNOSTICS
If the dump requires more than one tape, it will ask you to
change tapes. Reply with a new-line when this has been
done. If the first block on the new tape is not writable,
e.g. because you forgot the write ring, you get a chance to
fix it. Generally, however, read or write failures are
fatal.
FILES
/dev/mt0 magtape
/dev/rp0 default file system
/etc/dtab
SEE ALSO
restor (VIII), ncheck (VIII), dump (V)
BUGS
2