Backup Manager 0.7.7 User Guide
                      -------------------------------

                              Alexis Sukrieh

                            1.7 - 14 Apr, 2008


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Copyright Notice
----------------

     copyright (C) 2005 Alexis Sukrieh

     This user guide is free software; you may 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 was
     merchantability or fitness for a particular purpose.  See the GNU
     General Public License for more details.

     A copy of the GNU General Public License is available on the World
     Wide Web at the GNU web site (http://www.gnu.org/copyleft/gpl.html).
     You can also obtain it by writing to the Free Software Foundation,
     Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.


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Contents
--------

     1.        About this manual
     1.1.      Scope
     1.2.      Version
     1.3.      Authors

     2.        Configuration files
     2.1.      Repository and Archives
     2.1.1.         The Repository
     2.1.2.         Encryption
     2.1.3.         Archives
     2.2.      Backup Methods
     2.2.1.         Tarballs
     2.2.2.         Incremental tarballs
     2.2.3.         MySQL databases
     2.2.4.         Subversion repositories
     2.2.5.         Generic methods
     2.3.      Upload Methods
     2.3.1.         Description
     2.3.2.         Global configuration keys
     2.3.3.         SSH uploads
     2.3.4.         Encrypted SSH uploads
     2.3.5.         FTP uploads
     2.3.6.         Amazon S3 uploads
     2.3.7.         RSYNC uploads
     2.4.      Exports
     2.4.1.         Burning CDR/DVD media
     2.5.      Advanced features
     2.5.1.         `BM_TEMP_DIR'
     2.5.2.         Logging to syslog
     2.5.3.         Writing external hooks

     3.        Using Backup Manager
     3.1.      Command line
     3.1.1.         Restrictions
     3.1.2.         Options
     3.2.      CRON integration


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1. About this manual
--------------------


1.1. Scope
----------

     Backup Manager is a system tool designed to handle backups.  It is
     written with simplicity in mind.

     If you want to handle a couple of tarballs, reading the default
     configuration file might be enough to understand the main design.  On
     the other hand, if you want to know more about the global design of
     the program, how to write your own backup methods or even look at some
     real life examples, this guide is for you.

     This document describes the main design of the software and gives
     information about supported configuration keys.  All backup methods
     are described, with a sample configuration file as illustration.
     Whenever possible, advices and best practices are given.

     This manual also describes every configuration variables supported in
     the version 0.7.7.


1.2. Version
------------

     This document is updated whenever a new release of Backup Manager is
     published.  The current version covers all features and configuration
     details about version 0.7.7.

     The first version of this document was written with the release 0.6 of
     Backup Manager.


1.3. Authors
------------

     The first version of this document was made in late 2005, by Alexis
     Sukrieh and has been reviewed by Sven Joachim.

     While the author of this document has tried hard to avoid typos and
     other errors, these do still occur.  If you discover an error in this
     manual or if you want to give any comments, suggestions, or criticisms
     please send an email to the development list,
     backup-manager-devel@backup-manager.org, or submit a bug report
     against the "Documentation" product, in the bug tracking system[1].

[1]  http://bugzilla.backup-manager.org/


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2. Configuration files
----------------------

     _Backup Manager's behaviour is defined in configuration files.  You
     can run Backup Manager with different configuration files (at the same
     time or not).  This chapter will cover all the configuration keys
     supported in version 0.7.7 and will explain their meaning._


2.1. Repository and Archives
----------------------------

     Backup Manager stores _archives_ it builds in a _repository_.
     _Archives_ are built by using a _backup method_.

2.1.1. The Repository
---------------------

2.1.1.1. `BM_REPOSITORY_ROOT'
-----------------------------

     _Type: string, default: `/var/archives'._

     The repository is the place in your filesystem where all archives are
     stored.  This is a particular place for Backup Manager, it will be
     cleaned during backup sessions: archives older than the authorized
     lifetime will be purged.  If the repository does not exist, it will be
     created at runtime.

     Isolating the repository on a dedicated partition is a good idea.
     This can prevent the repository from eating all the disk space of the
     partition.  With a bad configuration file, backup sessions can lead to
     huge archives, for many reasons, so take care.

     Example:

          export BM_REPOSITORY_ROOT="/var/archives"

2.1.1.2. `BM_REPOSITORY_SECURE'
-------------------------------

     _Type: boolean, default: `true'._

     For security reasons, the repository can be accessible by a specific
     user/group pair.  This will prevent the archives from being readable
     (and writable) by any user in the system.  This mode is enabled by
     default (owned by `root:root').

     To enable this mode, set the configuration key `BM_REPOSITORY_SECURE'
     to `yes', then update `BM_REPOSITORY_USER' and `BM_REPOSITORY_GROUP'
     to your needs.

     You can also change the permission of the repository and the archives,
     that is possible with two configuration variables:
     `BM_REPOSITORY_CHMOD' and `BM_ARCHIVE_CHMOD'.

     Example:

          export BM_REPOSITORY_SECURE="true"
          export BM_REPOSITORY_USER="root"
          export BM_REPOSITORY_GROUP="root"
          export BM_REPOSITORY_CHMOD="770"
          export BM_ARCHIVE_CHMOD="660"

2.1.2. Encryption
-----------------

     _If you cannot trust the place where you store your archives, you can
     choose to encrypt them so you are the only one who can read their
     content.  That's a very good idea for archives you plan to upload to
     some remote place, or even for the archives you want to daily export
     on removable media._

2.1.2.1. `BM_ENCRYPTION_METHOD'
-------------------------------

     _Type: string, default: undefined._

     For Backup Manager, encryption is defined in one place in the
     configuration file.  If the variable "`BM_ENCRYPTION_METHOD'" is not
     defined, no encryption occurs during the archive build process, if a
     method is defined there, then any archive built are encrypted through
     a pipeline with that method.

     Be aware that encryption is supported for the methods "mysql", "pipe",
     "tarball" and "tarball-incremental" but only for those file types:
     tar, tar.gz, tar.bz2.

     The only valid method supported for encrypting archives is "gpg".

     Backup Manager will encrypt your archive through a pipeline in order
     not to write any byte of unencrypted data on the physical media.  The
     encryption will be performed with a command line like the following:

          <command> | gpg -r "$BM_ENCRYPTION_RECIPIENT" -e > archive.gpg

     To decrypt an archive built with GPG encryption, you have to be the
     owner of the private GPG key for which the encryption was made.  Then
     issue the following:

          $ gpg -d <archive.gpg> > archive

     GPG will then prompt you for the private key passphrase and will
     decrypt the content of the archive if the passphrase is valid.

     Refer to the GPG documentation for more details of encryption.

2.1.2.2. `BM_ENCRYPTION_RECIPIENT'
----------------------------------

     _Type: string, default: undefined._

     As explained in the previous section, that variable should contain the
     GPG recipient for the encryption, eg: your GPG ID.

     Examples of valid GPG ID:

          export BM_ENCRYPTION_RECIPIENT="0x1EE5DD34"
          export BM_ENCRYPTION_RECIPIENT="Alexis Sukrieh"
          export BM_ENCRYPTION_RECIPIENT="sukria@sukria.net"

2.1.3. Archives
---------------

     _Archives are produced by backup methods, they can be virtually
     anything, but will always be named like the following:
     `prefix-name-date.filetype'.  An archive is a file that contains data,
     it can be compressed or not, in a binary form or not._

2.1.3.1. `BM_ARCHIVE_STRICTPURGE'
---------------------------------

     _Type: boolean, default: `true'._

     As explained in the BM_REPOSITORY_ROOT section, every archive built by
     Backup Manager will be purged when their lifetime expires.  In
     versions prior to 0.7.6, any archive were purged.

     You can now choose to purge only the archive built in the scope of the
     configuration file, that is: archives prefixed with BM_ARCHIVE_PREFIX.

     This is useful if you share the same BM_REPOSITORY_ROOT with different
     instances of Backup Manager that have different purging rules (eg: a
     BM_REPOSITORY_ROOT shared over NFS for multiple Backup Manager
     configuration).

     Example:

          export BM_ARCHIVE_STRICTPURGE="true"

2.1.3.2. `BM_ARCHIVE_NICE_LEVEL'
--------------------------------

     _Type: string, default: `10'._

     Backup Manager does handle several archive methods, which can use a
     lot of ressources (mostly CPU); although this can be acceptable if
     Backup Manager is run at night, on a always-running server, it can
     seriously slow-down a desktop computer.  Indeed, most of the time,
     desktop users use anacron to run backup-manager when possible, and
     most of time this is when the desktop is actually used.

     To enhance the desktop-experience when archives are built, you can
     adjust the niceness used for archive creation with this configuration
     variable.

     To set a low priority to the archive creation processes, use a high
     number (max: 19).  See the manpage of nice for details.

     Example:

          export BM_ARCHIVE_PURGEDUPS="19" # recommanded for desktop users.

2.1.3.3. `BM_ARCHIVE_PURGEDUPS'
-------------------------------

     _Type: boolean, default: `true'._

     If disk usage matters in your backup strategy, you might find useful
     to use Backup Manager's duplicates purging feature.  When an archive
     is generated, Backup Manager looks at the previous versions of this
     archive.  If it finds that a previous archive is the same file as the
     one it has just built, the previous one is replaced by a symlink to
     the new one.  This is useful if you don't want to have the same
     archive twice in the repository.

     Example:

          export BM_ARCHIVE_PURGEDUPS="true"
          
          host-etc.20051115.tar.gz
          host-etc.20051116.tar.gz -> /var/archives/host-etc.20051117.tar.gz
          host-etc.20051117.tar.gz

2.1.3.4. `BM_ARCHIVE_TTL'
-------------------------

     _Type: integer, default: `5'._

     One of the main concepts behind the handling of the repository is to
     purge deprecated archives automatically.  The purge session is always
     performed when you launch Backup Manager.  During this phase, all
     archives older than the authorized lifetime are dropped.

     Since version 0.7.3, Backup Manager purges only files it has created
     whereas in previous versions, it used to purge also other files within
     the repository.

     Note that when using the incremental method for building archives,
     Backup Manager will handle differently master backups and incremental
     ones.  The incremental backups will be purged like any other archives
     (when exceeding the authorized lifetime).  On the ohter hand,
     deprecated master backups won't be purged unless there is a younger
     master backup in the repository.  Then, even with a lifetime set to
     three days, a master backup will live more than three days, until a
     newer master backup is built.

     Example:

          export BM_ARCHIVE_TTL="5"

2.1.3.5. `BM_REPOSITORY_RECURSIVEPURGE'
---------------------------------------

     _Type: boolean, default: `false'._

     On most setups, all the archives are stored in the top-level directory
     specified by the configuration key `BM_REPOSITORY_ROOT'.  But it can
     make sense to have subdirectories, for instance to store archives
     uploaded from other hosts running Backup Manager.  In this case, it is
     possible to ask Backup Manager to purge those directories too, by
     setting `BM_REPOSITORY_RECURSIVEPURGE' to `true'.

     Please note that the `BM_ARCHIVE_TTL' value is global, so if you want
     to have different lifetimes for some archives, this is not the way to
     go.  In this case you should save them outside `BM_REPOSITORY_ROOT'
     and write a cron job to do the purge (possibly calling `backup-manager
     --purge' with an alternate configuration file).

     Example:

          export BM_REPOSITORY_RECURSIVEPURGE="false"

2.1.3.6. `BM_ARCHIVE_PREFIX'
----------------------------

     _Type: string, default: `$HOSTNAME'._

     This is the prefix used for naming archives.

     Example:

          export BM_ARCHIVE_PREFIX="$HOSTNAME"
          
          # echo $HOSTNAME
          ouranos
          # ls /var/archives
          ouranos-20051123.md5
          ouranos-usr-local-src.20051123.tar.gz
          ouranos-etc.20051123.tar.gz


2.2. Backup Methods
-------------------

     The core feature of Backup Manager is to make archives, for doing
     this, a _method_ is used.  Each method can require a set of
     configuration keys.  We will describe here every method supported in
     the version 0.7.7.

     The method you choose must be defined in the configuration key
     `BM_ARCHIVE_METHOD'.  You can put here a list of all the different
     methods you want to use.  Take care to put every configuration key
     needed by all the methods you choose.  Note that you can also choose
     none of the proposed methods, if you don't want to build archives with
     this configuration file, then just put `none'.

     A couple of other configuration keys may be needed depending on the
     method you choose.

     Example:

          export BM_ARCHIVE_METHOD="tarball-incremental mysql"

2.2.1. Tarballs
---------------

2.2.1.1. Description
--------------------

     _Method name: `tarball', configuration key prefix: `BM_TARBALL'._

     If all you want to do is to handle a couple of tarballs of your file
     system, you can use this method.  This method takes a list of
     directories and builds the corresponding tarballs.  This method is the
     default one, this is the easiest to use, it just builds tarballs as
     you could do with your own tar script.  Its main drawback is to eat a
     lot of disk space: archives can be big from a day to another, even if
     there are no changes in their content.  See the `tarball-incremental'
     method if you want to optimize archives' size.

     When building full backups (when not building incremental ones),
     Backup Manager will append the keyword "master" to the name of the
     archive.  This is very useful when using the `tarball-incremental'
     method for seeing where the full backups are quickly.

     A couple of options are available: the name format of the archive, the
     compression type (gzip, zip, bzip2, none) and the facility to
     dereference symlinks when building the tarball.

2.2.1.2. `BM_TARBALL_NAMEFORMAT'
--------------------------------

     This configuration key defines how to perform the naming of the
     archive.  Two values are possible:

        * `long': the name will be made with the absolute path of the
          directory (eg: `var-log-apache' for `/var/log/apache').

        * `short': the name will just contain the directory (eg: `apache'
          for `/var/log/apache').

     Suggested value: `long'.

2.2.1.3. `BM_TARBALL_FILETYPE'
------------------------------

     _Type: enum(tar, tar.gz, tar.bz2, tar.lz, zip, dar), default:
     `tar.gz'._

     Basically, this configuration key defines the filetype of the
     resulting archive.  In a way, it defines which compressor to use (zip,
     gzip, dar or bzip2).  Here are the supported values: `tar', `tar.gz',
     `tar.bz2', `zip' and `dar'.  Note that depending on the filetype you
     choose, you will have to make sure you have the corresponding
     compressor installed.

     For the best compression rate, choose `tar.bz2' or `tar.lz'.

     Since version 0.7.1, Backup Manager supports _dar_ archives.  This
     archiver provides some interesting features like the archive slicing.

     Since version 0.7.5, Backup Manager supports _lzma_ archives.

     Make sure to statisfy dependencies according to the filetype you
     choose:

        * tar.bz2 : needs "bzip2".

        * tar.lz : needs "lzma".

        * dar : needs "dar".

        * zip : needs "zip".

2.2.1.4. `BM_TARBALL_SLICESIZE'
-------------------------------

     _Type: string_

     If you want to make sure your archives won't exceed a given size (for
     instance 2 GB) you can use that configuration variable, but only if
     you are using the `dar' `BM_TARBALL_FILETYPE'.  Indeed this feature is
     only supported by dar.

     If you want to limit your archives size to 1 giga byte, use such a
     statement:

          BM_TARBALL_SLICESIZE="1000M"

     Refer to the dar manpage for details about slices.

2.2.1.5. `BM_TARBALL_EXTRA_OPTIONS'
-----------------------------------

     _Type: string_

     If you want to provide extra options to "tar" or "dar" you may do so
     here.  Leave blank unless you know what you are doing.

     Example: to enable verbosity with tar (which would appeard in the
     logfiles), use this:

          BM_TARBALL_EXTRA_OPTIONS="-v"

2.2.1.6. `BM_TARBALL_DUMPSYMLINKS'
----------------------------------

     _Type: boolean, default: `true'._

     It is possible, when generating the tarball (or the zip file) to
     dereference the symlinks.  If you enable this feature, every symbolic
     link in the file system will be replaced in the archive by the file it
     points to.  Use this feature with care, it can quickly lead to huge
     archives, or even worse: if you have a circular symlink somewhere,
     this will lead to an infinite archive!

     In most of the cases, you should not use this feature.

2.2.1.7. `BM_TARBALL_DIRECTORIES'
---------------------------------

     _Type: space-separated list, default: `null'._

     Since version 0.7.3, this variable is replaced by the array
     BM_TARBALL_TARGETS[], it's still supported for backward compatibility
     though.  You can use this variable for defining the locations to
     backup, but you must not use this variable if one or more of the paths
     you want to archive contain a space.

     If you want to backup some targets that have spaces in their name (eg
     "Program Files"), you must not use this variable, but the array
     BM_TARBALL_TARGETS[] instead.

     Example:

          export BM_TARBALL_DIRECTORIES="/etc /home /var/log/apache"

2.2.1.8. `BM_TARBALL_TARGETS'
-----------------------------

     _Type: array, default: `"/etc", "/boot"'._

     This variable holds every place you want to backup.  This is the
     recommanded variable to use for defining your backup targets
     (`BM_TARBALL_DIRECTORIES' is deprecated since version 0.7.3).

     You can safely put items that contain spaces (eg: "Program Files")
     whereas you can't with `BM_TARBALL_DIRECTORIES'.

     You can also put Bash patterns in BM_TARBALL_TARGETS[], it will be
     expanded at runtime to find the resulting targets.  For instance :
     BM_TARBALL_TARGETS[0]="/home/*" will lead to backup every home's
     sub-directory.

     Example

          BM_TARBALL_TARGETS[0]="/etc"
          BM_TARBALL_TARGETS[1]="/home/*"
          BM_TARBALL_TARGETS[2]="/boot"
          BM_TARBALL_TARGETS[3]="/mnt/win/Program Files"

2.2.1.9. `BM_TARBALL_BLACKLIST'
-------------------------------

     _Type: space-separated list, default: `"/proc /dev /sys /tmp"'._

     It can be very useful to prevent some locations of your filesytem from
     being included in the archives.  This is really useful when you use
     wildcards in BM_TARBALL_DIRECTORIES.  Indeed, you may want to backup
     every top-level directory of your filesystem (`/*') but without
     volatile locations like `/tmp', `/dev' and `/proc'.

     You can also use this variable for excluding every files of a given
     extension, like for instance mp3 or mpg files.

     Example:

          export BM_TARBALL_BLACKLIST="/tmp /dev /proc *.mp3 *.mpg"

2.2.1.10. `BM_TARBALL_OVER_SSH'
-------------------------------

     _Type: boolean, default: `false'._

     _Dependency: `BM_UPLOAD_SSH'_

     If you want to archive some remote locations from a server where
     Backup Manager is insalled, you can choose to build archives over SSH.
     This is useful if you don't want to install Backup Manager every where
     and setup some upload methods from all thoses servers to a central
     data storage server.  This way, Backup Manager will build some
     archives directly over SSH and will store the resulting tarballs
     locally, as if it was built like any other archive.  The resulting
     archive will be prefixed with the remote hostname instead of
     `BM_ARCHIVE_PREFIX'.

     This feature requires that the following variables are set in the
     BM_UPLOAD_SSH section:

        * `BM_UPLOAD_SSH_USER': the user to use for connecting to the
          remote server.  Note that this user will run tar remotely, so
          take care to archive something this user can read!

        * `BM_UPLOAD_SSH_KEY': as usal, the path to the private key to use
          for establishing the connection.

        * `BM_UPLOAD_SSH_HOSTS': A list of hosts where to run the tarball
          builds.

     If you enable this feature, note that the resulting configuration file
     will have the following restrictions:

        * Remote tarball build only works with the `tarball' method, it
          will silently behaves the same with `tarball-incremental'.

        * You cannot use the remote build and the local one in the same
          configuration file.  If you want to do both, use two
          configuration files.

     Example: You have three hosts: host01, host02 and host03.  You want to
     set up host01 as a data storage server, it has a big /var/archives
     partition.  You want to archive "/etc", "/home" and "/var/log" on
     box02 and box03 and store the archives on host01.

          [...]
          export BM_ARCHIVE_METHOD="tarball"
          
          export BM_TARBALL_OVER_SSH="true"
          export BM_TARBALL_FILETYPE="tar.bz2"
          export BM_TARBALL_DIRECTORIES="/etc /home /var/log"
          
          export BM_UPLOAD_SSH_USER="bamuser"
          export BM_UPLOAD_SSH_KEY="/home/bamuser/.ssh/id_dsa"
          export BM_UPLOAD_SSH_HOSTS="box02 box03"

     Of course, for this to work correctly, ``bamuser'' should be a valid
     user on box02 and box03; it must be allowed to connect to them with
     SSH key autentication and has to be able to read those directories.

2.2.2. Incremental tarballs
---------------------------

2.2.2.1. Description
--------------------

     _Method name: `tarball-incremental', configuration key prefix:
     `BM_TARBALLINC'._

     If you want to handle tarballs without wasting disk space, you should
     use this method.  The concept of this method is simple: You choose a
     frequency when a full backup is made (exactly like the one made by the
     tarball mehod).  All the days between two full backups, archives
     contain only the files that have changed from the previous archive.

     For instance, let's say you want to backup /home with this method.
     Your /home directory is composed by two sub-directories: /home/foo and
     /home/bar.  You choose a weekly frequency and say that monday will be
     the "fullbackup" day.  Obviously, you will have a full tarball of
     /home on monday.  Then, if a file changed inside /home/foo and if
     /home/bar remains unchanged, tuesday's archive will only contain the
     modified files of /home/foo.  Using this method will save a lot of
     disk space.

     To build incremental tarballs, Backup Manager uses tar's switch
     `--listed-incremental'.  This will create a file for each target which
     will contain some statistics used by tar to figure out if a file
     should be backed up or not.  When Backup Manager is run for the first
     time, this file doesn't exist, so the first tarballs made are always
     master backups.  If the _incremental list_ files get removed, the next
     backups won't be incremental.

     Since version 0.7.3, it's possible to see at the first glance if a
     backup is a master or an incremental one: master backup have the
     keyword `master' appended to the date.  When purging the repository,
     the master backups are not removed as the incremental ones.  Backup
     Manager always keep a master backup that is older than incremental
     archives.

     This method uses all the tarball's configuration keys and adds two
     more.  One to define the kind of frequency, the other to choose on
     which day the full backups should be done.

2.2.2.2. `BM_TARBALLINC_MASTERDATETYPE'
---------------------------------------

     _Type: enum(weekly, monthly), default: `weekly'._

     This is the type of frequency you want to use.  If you choose
     `weekly', you'll have to choose a day number between 0 and 6 for the
     BM_TARBALLINC_MASTERDATEVALUE configuration key, if you choose
     `monthly', the day number will be between 1 and 31.

2.2.2.3. `BM_TARBALLINC_MASTERDATEVALUE'
----------------------------------------

     _Type: integer, default: `1'._

     The number of the day when making full backups.  Note that its meaning
     directly depends on the `BM_TARBALLINC_MASTERDATETYPE'.  For instance,
     1 means _"monday"_ if you choose a weekly frequency, but it means
     _"the first day of the month"_ if you choose a monthly frequency.

2.2.3. MySQL databases
----------------------

2.2.3.1. Description
--------------------

     _Method name: `mysql', configuration keys prefix: `BM_MYSQL'._

     This method provides a way to archive MySQL databases, the archives
     are made with mysqldump (SQL text files) and can be compressed.

     In versions prior to 0.7.6, Backup Manager used to pass the MySQL
     client's password through the command line.  As explained by the MySQL
     manual, that's a security issue as the password is then readable for a
     short time in the /proc directory (or using the ps command).

     To close that vulnerability, the MySQL client password is not passed
     through the command line anymore, it is written in a configuration
     file located in the home directory of the user running Backup Manager
     : `~/.my.cnf'.

     If that file doesn't exist at runtime, Backup Manager will create it
     and will then write the password provided in `BM_MYSQL_ADMINPASS'
     inside.

2.2.3.2. `BM_MYSQL_DATABASES'
-----------------------------

     _Type: space-separated list, default: `__ALL__'._

     This is the list of databases you want to archive.  You can put the
     keyword `__ALL__' if you like to backup every database without having
     to list them.

     Example:

          export BM_MYSQL_DATABASES="mysql mybase wordpress dotclear phpbb2"

2.2.3.3. `BM_MYSQL_SAFEDUMPS'
-----------------------------

     _Type: boolean, default: `true'._

     The best way to produce MySQL dumps is done by using mysqldump's
     `--opt' switch.  This makes the dump directly usable with mysql (adds
     the drop table statements), locks tables during the dump generation
     and other cool things (see `mysqldump').  This is recommended for
     full-clean-safe backups, but needs a privileged user (for the lock
     permissions).

     Example:

          export BM_MYSQL_SAFEDUMPS="true"

2.2.3.4. `BM_MYSQL_ADMINLOGIN'
------------------------------

     _Type: string, default: `root'._

     The MySQL login you want to use for connecting to the database.  Make
     sure this login can read all the databases you've set in
     `BM_MYSQL_DATABASES'.

     Example:

          export BM_MYSQL_ADMINLOGIN="root"

2.2.3.5. `BM_MYSQL_ADMINPASS'
-----------------------------

     _Type: string, default: `undefined'._

     The MySQL client password.

     If you have already made your own ~/.my.cnf configuration file, you
     don't have to set that variable.

     If you don't know what is the `~/.my.cnf' configuration file, set the
     password, then Backup Manager will take care of creating the MySQL
     client configuration file.

     Example:

          export BM_MYSQL_ADMINPASS="MySecretPass"

2.2.3.6. `BM_MYSQL_HOST'
------------------------

     _Type: string, default: `localhost'._

     The database host where the databases are.

     Example:

          export BM_MYSQL_HOST="localhost"

2.2.3.7. `BM_MYSQL_PORT'
------------------------

     _Type: string, default: `3306'._

     The port on `BM_MYSQL_HOST' where the mysql server is listening.

     Example:

          export BM_MYSQL_PORT="3306"

2.2.3.8. `BM_MYSQL_FILETYPE'
----------------------------

     _Type: enum(gzip, bzip2), default: `bzip2'._

     The archive is made with mysqldump which renders SQL lines; the
     resulting text file can be compressed.  If you want to compress the
     file, choose the compressor you want.  Leave it blank if you want pure
     SQL files.

     Example:

          export BM_MYSQL_FILETYPE="bzip2"

2.2.4. Subversion repositories
------------------------------

2.2.4.1. Description
--------------------

     You can archive Subversion repositories with this method.  The archive
     will be made with `svnadmin' and will contain XML data (text files).
     Like the mysql method, you can choose to compress it.

2.2.4.2. `BM_SVN_REPOSITORIES'
------------------------------

     _Type: space-separated list_

     This is the list of absolute paths to the SVN repositories to archive.

     Example:

          export BM_SVN_REPOSITORIES="/srv/svnroot/repo1 /srv/svnroot/repo2"

2.2.4.3. `BM_SVN_COMPRESSWITH'
------------------------------

     _Type: enum(gzip, bzip2), default: `bzip2'._

     If you want to compress the resulting XML files, choose a compressor
     here.  Leave this blank if you don't want any compression.

     Example:

          export BM_SVN_COMPRESSWITH="gzip"

2.2.5. Generic methods
----------------------

2.2.5.1. Description
--------------------

     Even if most of the common needs are covered by the existing methods,
     there is always a case uncovered.  Backup Manager provides a way for
     backing up anything, and can be used in such circumstances.

     This method is called `pipe', it is more complex to use but can
     virtually backup anything.  The concept is simple, a pipe method is
     defined by the following items:

        * A name (for naming the archive)

        * A command (that produces content on stdout)

        * A file type (txt, sql, dump, ...)

        * A compressor (gzip, bzip2)

     Those configuration keys are arrays, so you can implement as many pipe
     methods as you like.

     For each pipe method defined, Backup Manager will launch the command
     given and redirect the content sent to stdout by this command to a
     file named with the name of the method and its filetype.  Then, if the
     method uses a compressor, the file will be compressed.

2.2.5.2. Example
----------------

     Example for archiving a remote MySQL database through SSH:

          BM_PIPE_COMMAND[0]="ssh host -c \"mysqldump -ufoo -pbar base\""
          BM_PIPE_NAME[0]="base"
          BM_PIPE_FILETYPE[0]="sql"
          BM_PIPE_COMPRESS[0]="gzip"

     Imagine you have a second pipe method to implement, for instance
     building a tarball trough SSH:

          BM_PIPE_COMMAND[1]="ssh host -c \"tar -c -z /home/user\""
          BM_PIPE_NAME[1]="host.home.user"
          BM_PIPE_FILETYPE[1]="tar.gz"
          BM_PIPE_COMPRESS[1]=""

     Note that we have incremented the array's index.


2.3. Upload Methods
-------------------

2.3.1. Description
------------------

     _One of the most important thing to do when backing up file systems is
     to store the archives on different places.  The more different
     physical spaces you have, the better.  Backup Manager provides a way
     for achieving this goal : the upload methods._

     There are different upload methods, each of them behaves differently
     and provides particular features.  In Backup Manager 0.7.7 you can use
     FTP, SSH, RSYNC or Amazon S3 uploads.

     In the same manner as for backup methods, you can choose to use as
     many upload methods as you like.  If you don't want to use this
     feature at all, just put the keyword `none' in the configuration
     `BM_UPLOAD_METHOD'.

     Note that the FTP, SSH and S3 methods are dedicated to upload
     archives, using those method depends on the use of at least one backup
     method.

     On the opposite, the RSYNC method uploads a directory to remote
     locations, this directory can be your repository or whatever other
     location of your file sytem.

2.3.2. Global configuration keys
--------------------------------

     The following configuration keys are global in the upload section:

2.3.2.1. `BM_UPLOAD_HOSTS'
--------------------------

     _Type: space-separated list_

     Each of the hosts defined in that list is used by all the upload
     methods when establishing connections.  For instance if you want to
     perform SSH uploads of your archives and RSYNC upload of a location to
     the same host, put it in this list.

     Example:

export BM_UPLOAD_HOSTS="mirror1.lan.mysite.net mirror2.lan.mysite.net"

2.3.2.2. `BM_UPLOAD_DESTINATION'
--------------------------------

     _Type: string_

     This is the absolute path of the directory in the remote hosts where
     to put the files uploaded.

     If you have installed installed Backup Manager on the remote host, a
     good idea is to choose a sub-directory of the repository.  Then,
     during the remote host purge phase, your uploads will be cleaned at
     the same time.

     You can also define a destination dedicated to your host:
     `BM_UPLOAD_DESTINATION="/var/archives/$HOSTNAME"'

     Example:

     Let's say you want that all your uploads are performed on the host
     mirror2.lan.mysite.net, in the sub-directory /var/archives/uploads

          export BM_UPLOAD_HOSTS="mirror2.lan.mysite.net"
          export BM_UPLOAD_DESTINATION="/var/archives/uploads"

2.3.3. SSH uploads
------------------

2.3.3.1. Description
--------------------

     _Method name: `ssh', goal: upload archives to remote hosts over SSH.
     This method depends on a backup method._

     If you want to upload your archives on remote locations, you can use
     the SSH method.  This method is good if you like to use a secure
     tunnel between the two points of the upload.

     The call to `scp' will be done with the identity of the user
     `BM_UPLOAD_SSH_USER', thus, you have to make sure this user can have
     access to the repository (take care to the secure mode).

2.3.3.2. `BM_UPLOAD_SSH_USER'
-----------------------------

     _Type: string_

     This is the user to use for performing the ssh connection.  Make sure
     this user can access repository.

     Example:

          export BM_UPLOAD_SSH_USER="bmngr"

2.3.3.3. `BM_UPLOAD_SSH_KEY'
----------------------------

     _Type: string_

     This is the path to the private key of the user BM_UPLOAD_SSH_USER.

     Example:

          export BM_UPLOAD_SSH_KEY="/home/bmngr/.ssh/id_dsa"

2.3.3.4. `BM_UPLOAD_SSH_PORT'
-----------------------------

     _Type: integer_

     You may want to connect to remote hosts with a specific port.  Use
     this configuration key then.

     Example:

          export BM_UPLOAD_SSH_PORT="1352"

2.3.3.5. `BM_UPLOAD_SSH_HOSTS'
------------------------------

     _Type: space-separated list_

     Put here the list of hosts to use for SSH-only uploads.  Note that if
     you put some hosts in `BM_UPLOAD_HOSTS', they will be used as well.

     Example:

          export BM_UPLOAD_SSH_HOSTS="mirror3.lan.mysite.net"

2.3.3.6. `BM_UPLOAD_SSH_PURGE'
------------------------------

     _Type: boolean_

     If you set this boolean to "true", the remote archives will be purged
     before the new ones are uploaded.  The purging rules are the same as
     the ones Backup Manager uses for local purging.  If
     `BM_UPLOAD_SSH_TTL' is defined, this time to live will be used, else
     `BM_ARCHIVE_TTL' will be used.

     Example:

          export BM_UPLOAD_SSH_PURGE="true"
          export BM_UPLOAD_SSH_TTL="10"

2.3.3.7. `BM_UPLOAD_SSH_DESTINATION'
------------------------------------

     _Type: string_

     Put here the destination for SSH-only uploads, this key overrides
     `BM_UPLOAD_DESTINATION'.

     Example:

          export BM_UPLOAD_SSH_DESTINATION="/var/archives/scp-uploads"

2.3.4. Encrypted SSH uploads
----------------------------

2.3.4.1. Description
--------------------

     _Method name: `ssh-gpg', goal: encrypt arcives using public key
     encryption and upload the result to untrusted remote hosts over SSH.
     This method depends on a backup method._

     The upload using SSH can also be combined with public key encryption
     provided by `gpg'.  The archives will be encrypted using a public key
     prior to sending them over the network, so on the remote server your
     files are protected from inspection.

     This method can be used to protect your data from inspection on
     untrusted remote servers.  However, since the encrypted files are not
     signed, this does not protect you from archive manipulation.  So the
     _md5_ hases are still needed.

     This method uses all of the configuartion keys of the _ssh_ method.
     One additional key is required.

2.3.4.2. `BM_UPLOAD_SSH_GPG_RECIPIENT'
--------------------------------------

     _Type: string_

     This parameter sets the recipient for which the archive is encrypted.
     A valid specification is a short or long key id, or a descriptive
     name, as explained in the `gpg' man page.  The public key for this
     identity must be in the key ring of the user running `gpg', which is
     the same as specified by `BM_UPLOAD_SSH_USER'.  To test this run the
     command `gpg --list-keys ID' as that user, where `ID' is the ID as you
     give it to this parameter.  If `gpg' displays exactly one key, then
     you are fine.  Refer to the `gpg' man page for further details.

     Example:

          export BM_UPLOAD_SSH_GPG_RECIPIENT="email@address.com"
          export BM_UPLOAD_SSH_GPG_RECIPIENT="ECE009856"

2.3.5. FTP uploads
------------------

2.3.5.1. Description
--------------------

     If security does not matter much on your lan (between the two points
     of the upload) you can choose to use the FTP method.  One of the main
     pros of this method is that it can perform purging independently.  You
     can safely use this method for uploading files to a host where you
     just have an FTP account.

2.3.5.2. `BM_UPLOAD_FTP_SECURE'
-------------------------------

     _Type: boolean, default: false._

     If this variable is set to true, all FTP transfers will be done over
     SSL.

     Example:

          export BM_UPLOAD_FTP_SECURE="true"

2.3.5.3. `BM_UPLOAD_FTP_PASSIVE'
--------------------------------

     _Type: boolean, default: true._

     If this variable is set to true, FTP transfers will be performed in
     passive mode, which is mandatory in NATed/firewalled environments.

     Example:

          export BM_UPLOAD_FTP_PASSIVE="true"

2.3.5.4. `BM_UPLOAD_FTP_TTL'
----------------------------

     _Type: integer, default: $BM_ARCHIVE_TTL_

     Using different _time to live_ values for local and remote archives
     can be useful in certain situations.  For instance, it's possible to
     install Backup Manager locally, make it build archives, upload them to
     a remote FTP host and then purge them locally (but not on the remote
     host).  Doing this is possible with setting a null value to the local
     TTL (BM_ARCHIVE_TTL) and a non-null value to BM_UPLOAD_FTP_TTL.

     Example:

# in your main conffile -- /etc/backup-manager.conf
export BM_ARCHIVE_TTL="0"
export BM_UPLOAD_FTP_TTL="5"
export BM_POST_BACKUP_COMMAND="/usr/sbin/backup-manager --purge"

# in your cron job:
/usr/sbin/backup-manager
/usr/sbin/backup-manager --purge

(Don't put the post-command in the main conffile or you'll face an infinite loop.)

2.3.5.5. `BM_UPLOAD_FTP_USER'
-----------------------------

     _Type: string._

     Put here the FTP user to use for opening the connections.

     Example:

          export BM_UPLOAD_FTP_USER="bmngr"

2.3.5.6. `BM_UPLOAD_FTP_PASSWORD'
---------------------------------

     _Type: string._

     Put here the password to use for authenticating the FTP session,(in
     plain text).

     Example:

          export BM_UPLOAD_FTP_PASSWORD="secret"

2.3.5.7. `BM_UPLOAD_FTP_HOSTS'
------------------------------

     _Type: space-separated list_

     Put here the list of hosts to use for FTP-only uploads.  Note that if
     you put some hosts in `BM_UPLOAD_HOSTS', they will be used as well.

     Example:

          export BM_UPLOAD_FTP_HOSTS="mirror4.lan.mysite.net"

2.3.5.8. `BM_UPLOAD_FTP_DESTINATION'
------------------------------------

     _Type: string_

     Put here the destination for FTP-only uploads, this key overrides
     `BM_UPLOAD_DESTINATION'.

     Example:

          export BM_UPLOAD_FTP_DESTINATION="/var/archives/ftp-uploads"

2.3.5.9. `BM_UPLOAD_FTP_PURGE'
------------------------------

     _Type: boolean, default: `true'_

     You can choose to purge deprecated archives before uploading new ones.
     This purge is done over FTP and uses the configuration key
     `BM_ARCHIVE_TTL' in the same manner as the local purge behaves (the
     FTP purge is not recursive though).

     Example:

          export BM_UPLOAD_FTP_PURGE="true"

2.3.6. Amazon S3 uploads
------------------------

2.3.6.1. Description
--------------------

     Amazon's new Simple Storage Service (S3) is an Internet "web service"
     that permits you to store unlimited blocks of data on their replicated
     and managed systems.  See http://aws.amazon.com for more information.
     Registration is free and the rates are quite reasonable.

     Using the S3 upload method will permit your archives to be stored on
     Amazon's S3 service.  You must allocate a "bucket" to the exclusive
     use of Backup Manager.  Each of your created archives will be uploaded
     to S3 and stored within this bucket in a key name that matches the
     name of the archive.

     As with the other backup methods Backup Manager does not assist you in
     restoring files from archives.  You must retrieve archives from S3
     using other mechanisms such as the S3Shell provided as an examle
     command line utility by Amazon.

     Note that when using this upload method, the `BM_UPLOAD_HOSTS'
     variable is ignored as the only valid host for S3 uploads in
     `s3.amazon.com'.

2.3.6.2. `BM_UPLOAD_S3_DESTINATION'
-----------------------------------

     _Type: string._

     This option is required for the S3 upload method.  This specifies the
     bucket used to store backup data.  If the bucket does not exist it
     will be created as a private bucket.  This key overrides
     `BM_UPLOAD_DESTINATION'.  Note that Amazon requires that bucket names
     be globally unique.  Be creative picking one.

     Example:

          export BM_UPLOAD_S3_DESTINATION="my_backup_bucket"

2.3.6.3. `BM_UPLOAD_S3_ACCESS_KEY'
----------------------------------

     _Type: string._

     This option is required for the S3 upload method.  After you have
     registered Amazon will provide you an access key.  You must use this
     key to access your storage on S3.

     Example:

          export BM_UPLOAD_S3_ACCESS_KEY="a9sabkz0342dasv"

2.3.6.4. `BM_UPLOAD_S3_SECRET_KEY'
----------------------------------

     _Type: string._

     This option is required for the S3 upload method.  After you have
     registered Amazon will provide you a secret key.  You must use this
     key to write to your storage on S3.

     Example:

          export BM_UPLOAD_S3_SECRET_KEY="lkj2341askj123sa"

2.3.6.5. `BM_UPLOAD_S3_PURGE'
-----------------------------

     _Type: boolean, default: `true'_

     You can choose to purge deprecated archives before uploading new ones.
     This purge is done over S3 and uses the configuration key
     `BM_ARCHIVE_TTL' in the same manner as the local purge behaves (the S3
     purge is not recursive though).

     Example:

          export BM_UPLOAD_S3_PURGE="true"

2.3.7. RSYNC uploads
--------------------

2.3.7.1. Description
--------------------

     You may want to upload some parts of your file system to some remote
     hosts.  In these cases, archives are not needed, you just want to
     synchronize some directories to remote places.  This is where the
     RSYNC upload method is useful.

     RSYNC uploads need a SSH user/key pair to behave correctly, thus there
     is a dependency against the keys `BM_UPLOAD_SSH_USER' and
     `BM_UPLOAD_SSH_KEY'.

2.3.7.2. `BM_UPLOAD_RSYNC_DIRECTORIES'
--------------------------------------

     _Type: space-separated list_

     Put here the list of local directories you want to upload with rsync.

     Example:

export BM_UPLOAD_RSYNC_DIRECTORIES="/data/photos /data/videos /data/mp3"

2.3.7.3. `BM_UPLOAD_RSYNC_HOSTS'
--------------------------------

     _Type: space-separated list_

     Put here the list of hosts to use for RSYNC-only uploads.  Note that
     if you put some hosts in `BM_UPLOAD_HOSTS', they will be used as well.

     Example:

          export BM_UPLOAD_RSYNC_HOSTS="mirror5.lan.mysite.net"

2.3.7.4. `BM_UPLOAD_RSYNC_DESTINATION'
--------------------------------------

     _Type: string_

     Put here the destination for RSYNC-only uploads, this key overrides
     `BM_UPLOAD_DESTINATION'.

     Example:

          export BM_UPLOAD_RSYNC_DESTINATION="/var/archives/rsync-snapshots"

2.3.7.5. `BM_UPLOAD_RSYNC_DUMPSYMLINKS'
---------------------------------------

     _Type: boolean, default: `false'._

     You can choose to dereference files pointed by symlinks in your RSYNC
     snapshots.  This feature should be used with care.

     Example:

          export BM_UPLOAD_RSYNC_DUMPSYMLINKS="false"


2.4. Exports
------------

     _Another way of storing your archives to a safe place is to use
     external media._

     In version 0.7.7, only CDs and DVDs are supported as external media,
     so we will discuss in this section only the `BM_BURNING' features.
     Other exports are expected to come in next versions though.

2.4.1. Burning CDR/DVD media
----------------------------

     In the version 0.7.7, Backup Manager supports four different kinds of
     media: CDR, CDRW and DVD+R(W) and DVD-R(W).

2.4.1.1. `BM_BURNING_METHOD'
----------------------------

     Set the key `BM_BURNING_METHOD' to the method corresponding to the
     media you want to burn:

        * CDR

        * CDRW

        * DVD

        * DVD-RW

     In _non-interactive mode_ (when backup-manager is not lauchned from a
     terminal), any of these methods will try to put the whole archive
     repository in the media, if it does not fit in the media, it will try
     to put only the archives built on the day, if that's not possible,
     nothing will be burnt.

     In _interactive mode_ (when backup-manager is launched from a
     terminal), the whole repository will be burnt into as many media as
     needed.  When a medium is satured with archives, backup-manager will
     pause the process asking the user to put a new media inside.

     The `CDRW' and `DVD-RW' methods will first blank the media, so you can
     safely use these methods if you want to use the same medium several
     times.

     The `CDR' and `DVD' medthods won't blank the medium first (DVD+RW
     media doesn't need blanking, it's possible to re-burn data on-the-fly
     over such media)..

     DVD media are handled by the tool `dvd+rw-tools', problems can occur
     in CRON environment with `dvd+rw-tools' versions prior to `6.1', make
     sure to have `6.1' or later if you want to burn DVD media with Backup
     Manager.

     As usual, you can put `none' in order to disable the burning process.

     All those burning methods share the same configuration keys, so it's
     easy to switch from a medium to another.

2.4.1.2. `BM_BURNING_DEVICE'
----------------------------

     _Type: string, default: `/dev/cdrom'._

     This is mandatory for using the burning feature, it's the device to
     use for mounting the media.  It's needed by backup manager for
     performing the MD5 checks and for other needs.

     Example:

          export BM_BURNING_DEVICE="/dev/cdrom"

2.4.1.3. `BM_BURNING_DEVFORCED'
-------------------------------

     _Type: string_

     Backup Manager uses `cdrecord' for burning CDs.  If when you run
     `cdrecord -scanbus' you don't see your burning device, that means you
     will have to force the device in ATA mode.  To tell Backup Manager to
     do so, just put here the path to your device, and a switch will be
     appended to the cdrecord commandline like the following : `cdrecrord
     ...  dev=$BM_BURNING_DEVFORCED ...'.

     Leave this configuration key blank if you see your device with
     `cdrecord -scanbus', in this case, Backup Manager will use the default
     cdrecord device for burning CDR media.

     Example:

          export BM_BURNING_DEVFORCED="/dev/cdrom"

2.4.1.4. `BM_BURNING_ISO_FLAGS'
-------------------------------

     _Type: string, default: "-R -J"_

     Media burned with Backup Manager will be made using a Joliet disc
     image.  The flags defined in that variable will be appended to the
     mkisofs command lines in order to specify wich media image to use.

     The default value "-R -J" produces a Joliet image, if you want to make
     non-Joliet disc images, you can change these flags.  Refer to the
     manpage of mkisofs for details about possible disc images.

     Don't change that variable if you don't know what you're doing.

     Example:

          export BM_BURNING_ISO_FLAGS="-R -J"

2.4.1.5. `BM_BURNING_MAXSIZE'
-----------------------------

     _Type: integer, default: `700'._

     This is where you define the maximum size (in megabytes) of the media
     you will put in the device.  Here is the list of the common sizes:

        * CDR/CDRW: 650, 700, 800

        * DVD: 4700

     When Backup Manager looks in the repository for burning data, it will
     try to put the whole archive repository in the media.  If the
     summarized size of the repository does not fit in
     `BM_BURNING_MAXSIZE', Backup Manager will then try to put only the
     archives of the day.

     Example for a CD burner

          export BM_BURNING_METHOD="CDRW"
          export BM_BURNING_MAXSIZE="700"

     Example for a DVD burner:

          export BM_BURNING_METHOD="DVD"
          export BM_BURNING_MAXSIZE="4700"

2.4.1.6. `BM_BURNING_CHKMD5'
----------------------------

     _Type: boolean, default: `true'._

     If this boolean is set to a true value, every MD5 sum will be checked
     when the media is burned in order to make sure everything is ok.

     Note that you can choose to perform this checkup with the command
     switch `--md5check'.

     Example:

          exports BM_BURNING_CHKMD5="true"


2.5. Advanced features
----------------------

     _A couple of advanced features are provided, they will be covered in
     this section._

2.5.1. `BM_TEMP_DIR'
--------------------

     _Type: string, default: `/tmp/backup-manager'._

     This is the temporary directory where temporary files are created by
     Backup Manager.

     Example:

          export BM_ARCHIVE_CHMOD="/tmp/backup-manager"

2.5.2. Logging to syslog
------------------------

     If you want to log Backup Manager actions to syslog, you can enable
     the internal logger, this is done with the configuration key
     `BM_LOGGER'.  You are also able to choose which syslog facility to use
     thanks to the key `BM_LOGGER_FACILITY'.

2.5.2.1. `BM_LOGGER'
--------------------

     _Type: boolean, default: `true'._

     If this boolean is set to true, Backup Manager will log everything to
     syslog.

     Example:

          exports BM_LOGGER="true"

2.5.2.2. `BM_LOGGER_FACILITY'
-----------------------------

     _Type: string, default: `user'._

     You can specify here a syslog facility to use, this can be useful if
     you like to filter messages from Backup Manager to a special syslog
     file.

     Example:

          exports BM_LOGGER_FACILITY="cron"

2.5.3. Writing external hooks
-----------------------------

     You have the availability to write your own hooks if you want to
     automate some special beaviours within the Backup Manager process.
     You may like to mount over NFS your archive repository _before_ the
     backup session and unmount it after, or you may like to launch your
     own uploader script when the backup session is finished.

     In order to let you implement any solution you like, Backup Manager
     provides two different hooks: the _pre-command_ and _post-command_
     hooks.

2.5.3.1. `BM_PRE_BACKUP_COMMAND'
--------------------------------

     _Type: string_

     Put here the path to a program (or a shell command) to launch before
     the backup session.  If the command fails (exits with non zero value,
     or prints the keyword `false' on stdout) the backup session will stop.
     If the pre-command succeeds, the process can follow.

     Example with a basic shell command:

export BM_PRE_BACKUP_COMMAND="mount -t nfs mirror.lan.net:/exports/backups /var/archives"

     Example with a custom script:

export BM_PRE_BACKUP_COMMAND="/usr/local/bin/backup-prepare.pl $TODAY"

2.5.3.2. `BM_POST_BACKUP_COMMAND'
---------------------------------

     _Type: string_

     Put here the path to a program (or a shell command) to launch after
     the backup session.  If the command fails (exits with non zero value,
     or prints the keyword `false' on stdout) Backup Manager will exit with
     an error code (and will log to syslog the post-command failure if the
     logger is enabled).

     Example with a basic shell command:

          export BM_POST_BACKUP_COMMAND="umount /var/archives"

     Example with a custom script:

export BM_POST_BACKUP_COMMAND="/usr/local/bin/backup-cleanup.pl $TODAY"


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3. Using Backup Manager
-----------------------

     _Now that you know in details how to write your configuration files,
     let's see how to use Backup Manager._


3.1. Command line
-----------------

3.1.1. Restrictions
-------------------

     In version 0.7.7, Backup Manager can only be used by `root', as it has
     be designed as a systemwide tool.

          $ backup-manager
          backup-manager must be run as root.

     If you want to launch it from the command line, you first have to use
     the `root' account.

          $ su
          Password:
          # backup-manager -h
          /usr/sbin/backup-manager [options]
          
          Output:
          --help|-h           : Print this short help message.
          --verbose|-v        : Print what happens on STDOUT.
          --no-warnings       : Disable warnings.
          
          Single actions:
          --upload|-u         : Just upload the files of the day.
          --burn|-b           : Just burn the files of the day.
          --md5check|-m       : Just test the md5 sums.
          --purge|-p          : Just purge old archives.
          
          Behaviour:
          --conffile|-c file  : Choose an alternate config file.
          --force|-f          : Force overwrite of existing archives.
          
          Unwanted actions:
          --no-upload         : Disable the upload process.
          --no-burn           : Disable the burning process.
          --no-purge          : Disable the purge process.
          ouranos:/home/sukria#

     As you can see in the example above, using the `-h' switch (or
     `--help') gives a short help message and prints all supported command
     switches.  We will cover in this section each of them.

3.1.2. Options
--------------

     The following switches can be used for altering Backup Manager's
     behaviour.

3.1.2.1. `--version'
--------------------

     Prints on stdout the Backup Manager version installed on the system
     and exit.

     Example:

          # backup-manager --version
          Backup Manager 0.6

3.1.2.2. `--verbose' or `-v'
----------------------------

     Using this switch will enabled the verbose mode.  All actions are
     reported on stdout.

     Example:

# backup-manager -v
Getting lock for backup-manager 10605 with /etc/backup-manager.conf: ok
Cleaning /var/archives
Entering directory /var/archives/lost+found.
[...]

3.1.2.3. `--no-warnings'
------------------------

     When a non-critical problem occurs (an error occured but the backup
     process can follow) Backup Manager will print a warning message (and
     will log it if the logger is enabled).  If you don't want to see
     warning messages, you can append this switch on the command line.

3.1.2.4. `--conffile' or `-c'
-----------------------------

     Backup Manager relies on configuration files, by default, the file
     `/etc/backup-manager.conf' is used but you can choose to run it with a
     different one.  This is done by using the following syntax :

          # backup-manager -c <FILE>

     Note that Backup Manager is designed to work properly when launched in
     parallel mode with different configuration files, but it will refuse
     to run twice at the same time with the same configuration file.  You
     can then safely do something like that:

          # backup-manager -c /etc/backup-manager/backup-nfs.conf &
          # backup-manager -c /etc/backup-manager/backup-homedirs.conf &
          # backup-manager -c /etc/backup-manager/backup-rsync-filer.conf

3.1.2.5. `--force'
------------------

     When building an archive, Backup Manager looks if the archive already
     exists in the repository, if so, a warning is sent saying that the
     archive exists.  If you want to bypass this warning and overwrite
     archives, use this switch.

3.1.2.6. `--upload' or `-u'
---------------------------

     If you have made a configuration file that enables the uploading
     system, you can ask Backup Manager to perform the uploading session
     instead of the whole process with this switch.

3.1.2.7. `--burn' or `-b' [<DATE>]
----------------------------------

     If you have made a configuration file that enables the burning system,
     you can ask Backup Manager to perform the burning session instead of
     the whole process with this switch.

     You can also ask Backup Manager to burn only archives of a given date
     with providing a timestamp after the `--burn' switch.

     Example:

     Burning all the archives made on March, 12nd 2006:

          # backup-manager --bnurn 20060312

3.1.2.8. `--md5check' or `-m'
-----------------------------

     If you have made a configuration file that enables the MD5 checks on
     burnt media, you can ask Backup Manager to perform the MD5 checks
     instead of the whole process with this switch.

3.1.2.9. `--purge' or `-p'
--------------------------

     This switch will as Backup Manager to just perform the archive
     repository purge: removing any depreacted archives (according to
     `BM_ARCHIVE_TTL'.

3.1.2.10. `--no-upload' or `-p'
-------------------------------

     Use this switch if you have a configuration file that enables the
     uploading system and want to run Backup Manager without it.

3.1.2.11. `--no-burn'
---------------------

     Use this switch if you have a configuration file that enables the
     burning system and want to run Backup Manager without it.

3.1.2.12. `--no-purge' or `-p'
------------------------------

     Use this switch if you want to disable the purging phase.  This can be
     useful if you like to implement another kind of purging system, with a
     post-command hook for instance.


3.2. CRON integration
---------------------

     There is a global idea behind Backup Manager's design: "_You won't do
     it if you have to think about it_".  This is specifically true for
     backup concerns and it is strongly adviced to automate your backup
     process with a tasks scheduler like CRON.

     Setting up a Backup Manager job in cron is pretty easy, you just have
     to write a shell script under the appropriate CRON sub-directory that
     will call backup-manager.  The best sub-directory to choose is
     `/etc/cron.daily' as Backup Manager handles daily archives.

     Here is an example of a CRON script:

          cat > /etc/cron.daily/backup-manager
          #!/bin/sh
          
          /usr/sbin/backup-manager

     If you want to be notified by mail if a problem occurs during the
     backup session, just make sure you receive mails coming from CRON.
     When the verbose mode is off, only warnings and errors are printed on
     stdout, so you will receive a mail from the Backup Manager CRON job
     only in case of unexpected effects.

     On the other hand, if you like to receive daily mails from the job,
     even if everything went well, just append the --verbose switch like
     that :

          cat > /etc/cron.daily/backup-manager
          #!/bin/sh
          
          /usr/sbin/backup-manager --verbose


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     Backup Manager 0.7.7 User Guide

     Alexis Sukrieh


     1.7 - 14 Apr, 2008