.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved. The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\" @(#)dump.8 6.3 (Berkeley) 5/23/86
.\" @(#)dump.8 1.3 (UKC) %G%
.TH DUMP 8 "UKC altered %G%"
dump \- incremental file system dump
copies to magnetic tape all files
changed after a certain date
specifies the date and other options about the dump.
consists of characters from
This number is the `dump level'.
All files modified since the last date stored
for the same filesystem at lesser levels
If no date is determined by the level,
the beginning of time is assumed;
causes the entire filesystem to be dumped.
Place the dump on the next
If the name of the file is ``\-'',
writes to standard output.
If the dump completes successfully,
write the date of the beginning of the dump on
This file records a separate date for
each filesystem and each dump level.
is readable by people, consisting of one
free format record per line:
filesystem name, increment level
may be edited to change any of the fields,
The size of the dump tape is specified in feet.
The number of feet is taken from the next
When the specified size is reached,
will wait for reels to be changed.
The default tape size is 2300 feet.
The density of the tape, expressed in BPI,
This is used in calculating the amount of tape
used per reel. The default is 1600.
tells the operator what file systems need to be dumped.
This information is gleaned from the files
to print out, for each file system in
the most recent dump date and level,
and highlights those file systems that should be dumped.
option is set, all other options are ignored, and
Is like W, but prints only those filesystems which need to be dumped.
requires operator attention,
notify by means similar to a
all of the operators in the group \*(lqoperator\*(rq.
If no arguments are given,
and a default file system is dumped
This switch causes tapes to be rewound and the tape drive put offline after
each tape write has been done.
The next argument in the command list is a tape label.
The tape label is written into the dump file header at the beginning of each
tape which the dump uses.
Labels are currently limited to 15 characters.
The argument may contain a `%s', which is replaced by the volume number
in decimal of a multi-volume dump, unless the
argument is given (see below).
flag is set and the output device appears to be a tape drive,
The data written here contains the tape label, the
name of the file system which has been dumped, the date, the device
which was dumped, the dump level, the reel of the dump and the inode
which the dump started from.
The log is written just prior to the tape being written, this means that
bad tapes will be logged.
When a tape is overwritten, its old entry in the log file can be removed
by the shell script /etc/cleanvolumes.
The m argument provides a way of mapping the volume numbers of a multi-volume dump
into a series of strings.
argument, these strings become the tape label.
Otherwise the string is inserted in the tape label by the use of a `%s' marker
switch may be a single string or an auto-incrementing range.
These items may be grouped into a list by using commas to separate
An auto-incrementing range is two equal length strings separated by a minus
The first string is incremented starting at the rightmost character until
a match with the second string is acheived.
The increment treats the characters `0' to `9', `a' to `z', and `A' to `Z'
Examples to legal ranges are: 45-70, giving 45,46,47,48...69,70;
a00-b99, giving a00,a01,a02...b98,b99; and A0a-A9z, giving A0a,A0b,A0c...A9x,A9y,A9z.
will complain of the estimated number of tape which a dump will take is less
than the label range supplied by the user.
Tests that the tape being currently overwritten contains a header
bearing the correct label.
When a fresh tape is loaded, the first block is read and its label checked.
If the labels do not match, the write is refused on the tape.
This provides considerable protection and the ability to construct
may be used to label tapes prior to the use of
requires operator intervention on these conditions:
disk read error (if there are more than a threshold of 32).
In addition to alerting all operators implied by the
interacts with the operator on
control terminal at times when
or if something is grossly wrong.
be answered by typing \*(lqyes\*(rq or \*(lqno\*(rq,
Since making a dump involves a lot of time and effort for full dumps,
checkpoints itself at the start of each tape volume.
If writing that volume fails for some reason,
with operator permission,
restart itself from the checkpoint
after the old tape has been rewound and removed,
and a new tape has been mounted.
tells the operator what is going on at periodic intervals,
including usually low estimates of the number of blocks to write,
the number of tapes it will take, the time to completion, and
the time to the tape change.
so that others know that the terminal
and will be for some time.
Now a short suggestion on how to
Start with a full level 0 dump
Next, dumps of active file
systems are taken on a daily basis,
using a modified Tower of Hanoi algorithm,
with this sequence of dump levels:
For the daily dumps, a set of 10 tapes per dumped file system
is used on a cyclical basis.
Each week, a level 1 dump is taken, and
the daily Hanoi sequence repeats with 3.
For weekly dumps, a set of 5 tapes per dumped file system is
used, also on a cyclical basis.
Each month, a level 0 dump is taken
on a set of fresh tapes that is saved forever.
.ta \w'/etc/dumpvolumes\ \ 'u
/dev/rrp1g default filesystem to dump from
/dev/rmt8 default tape unit to dump to
/etc/dumpdates new format dump date record
/etc/dumpvolumes Listing of tape labels and the data which the tapes contain
/etc/fstab dump table: file systems and frequency
/etc/group to find group \fIoperator\fP
Dump exits with zero status on success.
Startup errors are indicated with an exit code of 1;
abnormal termination is indicated with an exit code of 3.
Fewer than 32 read errors on the filesystem are ignored.
Each reel requires a new process, so parent processes for
reels already written just hang around until the entire tape
options does not report filesystems that have never been recorded
in /etc/dumpdates, even if listed in /etc/fstab.
knew about the dump sequence,
kept track of the tapes scribbled on,
told the operator which tape to mount when,
and provided more assistance
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