-This is a quick summary of IWJ's backup scripts and my config files:
-it's a bit patchy and might have the odd ommission. The canonical
-source is the sources, as always :->
-
-
-WARNING - this file is out of date !
-
-# iwjbackup.txt
-# Documentation file
-#
-# This file is part of chiark backup, a system for backing up GNU/Linux and
-# other UN*X-compatible machines, as used on chiark.greenend.org.uk.
-#
-# chiark backup is:
-# Copyright (C) 1997-1998,2000-2001 Ian Jackson <ian@chiark.greenend.org.uk>
-# Copyright (C) 1999 Peter Maydell <pmaydell@chiark.greenend.org.uk>
-#
-# This is free software; you can redistribute it and/or modify it under the
-# terms of the GNU General Public License as published by the Free Software
-# Foundation; either version 2, or (at your option) any later version.
-#
-# This is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
-# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
-# details.
-#
-# You should have received a copy of the GNU General Public License along
-# with this program; if not, write to the Free Software Foundation, Inc.,
-# 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
-
-
-The three tarfiles in this directory should go in the following
-places (the paths can probably be configured/hacked, but this is
-where they are on my system and on chiark):
-
-etc.tgz : /etc/backup/
-lib.tgz : /usr/local/lib/backup/
-var.tgz : /var/local/backup/
-
-NOTE: these versions are not those used on chiark; they
-are somewhat modified by me (couple of extra features and
-lots of comments -- all errors in those are mine.)
-
-NB: you'll probably need to delete some of the files from
-var.tgz (in fact, I think you probably don't want any of
-them except maybe last-tape (which you want to change anyway).
-You'll also need to recompile readbuffer and writebuffer unless
-you're using SPARClinux :->
-
-Contents of /etc/backup/:
-warnings.* : files defining how many warnings you get as the
-system is brought down to do backups. The defaults are fine.
-settings.pl : generic config file: in particular, the name of
-the tape device is set here.
-tape.* : each tape you're going to use in the backup cycle
-has a name and a config file. Here the tapes are named 'a'-'e',
-although longer names should be OK. You need at least two
-tapes defined as the system won't write a backup on the same
-tape it wrote the last one to.
-
-Syntax of the tape.* files:
-filesystems X
-next N
-end
-
-where N is the next tape in the sequence (which should
-be circular; I have a->b->c->d->e->a...) and X is a
-filesystem-name (list of filesystems might work?).
-
-Each defined filesystem has a name and a config file
-fsys.<name>. These files define what is backed up and how.
-The filesystem 'all' must exist; it's used for incremental
-backups (and it must exist even if you don't do incrementals).
-I don't have any other filesystems defined as everything fits
-on one tape.
-
-Syntax of these files:
-Empty lines and lines starting '#' are comments and ignored.
-Lines starting 'excludedir' given regexps of things to exclude
-(temp dirs, Netscape's cache, etc).
-Lines starting 'prefix' give a command prefix necessary to
-run things on a remote machine:
-prefix <prefix-name> <command-part>
-Other lines should be of the form
-<directory name> <backup-type>
-for local backups, or
-<directory name> <backup-type> <prefix-name>
-for remote backups.
-The file must end with the word 'end' on a line of its own.
-
-Valid values for <backup-type> are 'cpio' (uses cpio to produce
-tar-format backups), 'dump' (uses dump to dump entire filesystems;
-<directory name> should be a mount-point for this), and [if you
-use my version of the scripts] 'zafio' (uses afio to compress
-each file as it is backed up). Only 'dump' type backups permit
-incremental backups.
-
-Finally, expected-diffs is a config file to indicate which
+iwjbackup.txt
+documentation file
+Copyright - AND NO WARRANTY - see notes at bottom of file for details.
+
+This is a quick summary of the backup scripts, and some comments on
+some of the config files: it's a bit patchy and might have the odd
+ommission. The canonical source is the sources, as always :->
+
+
+To run, the contents of /etc/chiark-backup should be:
+
+warnings.*: files defining how many warnings you get as the system is
+brought down to do backups. The defaults are fine.
+
+settings.pl: generic config file: in particular, the name of the tape
+device is set here.
+
+settings.sh: generic config file for shell scripts. Currently only
+contains some options for the lvm snapshotter.
+
+tape.*: conventionally, each tape you're going to use in the backup
+cycle has a tape number, a name and a config file. The tape numbers
+in use at Relativity are digit strings like `512'. The name is a
+combination of rotation set and volume number; rotation sets are
+typically a single letter (`s', `t', `u', `v') at Relativity and
+volumes a single digit (`0', `1', `2') at Relativity. You need at
+least two tapes as the system won't write a backup on the same tape it
+wrote the last one to.
+
+There are also conventionally incremental tapes whose names are a
+fixed letter (`k' in the current scheme) followed by a rotation
+letter. At Relativity we have two of these, `ks' and `kt'.
+
+Syntax of the tape.* files for full dump tapes:
+ filesystems X
+ next N
+ end
+
+where N is the name of the next tape in the *full dump* sequence
+(which should be circular; eg
+v0->v1->v2->s0->s1->s1->t0->t1->t2->u0->u1->u2->v0->...
+and X is a filesystem group name (typically the same as the volume
+number).
+
+Each defined filesystem group has a name and a config file
+fsys.<name>. These files define what is backed up and how. The
+filesystem `all' must also exist; it's used for incremental backups
+(and it must exist even if you don't do incrementals).
+
+In the fsys.* files:
+ Empty lines and lines starting '#' are comments and ignored.
+ Lines starting `excludedir' given regexps of things to exclude
+ (temp dirs, Netscape's cache, etc).
+ Lines starting `include' say to include another file when reading
+ this one.
+ Lines starting `prefix' give a command prefix necessary to
+ run things on a remote machine:
+ prefix <prefix-name> <command-part>
+ Other lines should be of the form
+ [<device name>:]<directory name> <backup-type>[,<options>]
+ for local backups, or
+ [<device name>:]<directory name> <backup-type>[,<options>] <prefix-name>
+ for remote backups.
+The file (including any included files) must end with the word 'end'
+on a line of its own.
+
+Valid values for <backup-type> are
+ cpio
+ uses cpio to produce tar-format backups
+ dump
+ uses dump to dump entire filesystems
+ <directory name> should be a mount-point
+ gtar
+ uses GNU tar to produce GNU tar format backups and -N-based
+ semi-incrementals (not --incremental or --listed-incremental)
+ zafio
+ uses afio to compress each file as it is backed up
+ ntfsimage
+ for NTFS volumes, requires device name
+Only `dump' and `gtar' type backups perform any kind of incremental
+backups.
+
+<options> is a comma-separated list of <option> or <option>=<value>.
+Options supported:
+
+ gz[i][=<compressionlevel>]
+ Indicates that the whole stream should be compressed with gzip.
+ The compression level defaults to 1 if gz is specified by the
+ level isn't. gzi appliies only to the incrementals; gz applies to
+ both unless gzi is also specified. compression level 0 means not
+ to run gzip at all and is the default if gz[i] is not mentioned.
+
+ snap=<snapkind>
+ Indicates that the filesystem should be frozen before the backup
+ by using /etc/chiark-backup/snap/<snapkind>. See the head comment
+ in /etc/chiark-backup/snap/lvm for details of how this works.
+ When snap= is used, the block device must be specified.
+
+expected-diffs is a config file to indicate which