ccollect/doc/ccollect.text

ccollect - Installing, Configuring and Using
============================================
Nico Schottelius <nico-linux-ccollect__@__schottelius.org>
v0.2, 2005-01-13
:Author Initials: NS

(pseudo) incremental backup
with different exclude lists
using hardlinks and `rsync`

Introduction
------------
ccollect is a backup utitily written in the sh-scripting language.
It does not depend on a specific shell, only `/bin/sh` needs to be
bourne shell compatibel (like 'dash', 'zsh' or 'bash').


Why you can only backup TO localhost
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
While thinking about the design of ccollect, I thought about enabling
backup to *remote* hosts. Though this sounds like a nice feature
('Backup my notebook to the server now.'), it is in my opinion a
bad idea to backup to a remote host, because you have to open
security at your backup host. Think of the following situation: You backup
your farm of webservers *to* a backup host somewhere else. One of
your webservers gets compromised, then your backup server will be compromised,
too. Think of it the other way round: The backup server (now behind a
firewall using NAT and strong firewall rules) connects to the
webservers and pulls the data to it. If someone gets access to the
webserver, the person will perhaps not even see your machine. If
he/she sees that there are connections from a host to the compromised
machine, he/she will not be able to login to the backup machine.
All other backups are still secure.


Requirements
------------

Installing ccollect
~~~~~~~~~~~~~~~~~~~

For the installation, you need at least
  - either 'cp' and 'chmod' or 'install
  - for more comfort: 'make'
  - for rebuilding the generated documentation: additionally 'asciidoc'


Using ccollect
~~~~~~~~~~~~~~
.Running ccollect requires the following tools installed:
   - `bc`
   - `cp` with support for hard links ('cp -al')
   - `rsync`
   - `ssh` (if you want to use rsync over ssh, which is recommened for security)


Installing
----------
Either type 'make install' or simply copy it to a directory in your
$PATH and execute 'chmod *0755* /path/to/ccollect.sh'.


Configuring
-----------

Runtime options
~~~~~~~~~~~~~~~
`ccollect` looks for its configuration in '/etc/ccollect' or, if set, in
the directory specified by the variable '$CCOLLECT_CONF'
(use 'CCOLLECT_CONF=/your/config/dir ccollect.sh' on the shell).

When you start `ccollect`, you have either to specify which intervall
to backup (daily, weekly, yearly; you can specify the names yourself, see below).

The intervall is used to specify how many backups to keep.

There are also some self explaining parameters you can pass to ccollect, simply use
"ccollect.sh --help" for info.


General configuration
~~~~~~~~~~~~~~~~~~~~~
The general configuration can be found below $CCOLLECT_CONF/defaults or
/etc/ccollect/defaults. All options specified here are generally valid for
all source definitions. Though the values can be overwritten in the source
configuration.

All configuration entries are plain-text (use UTF-8 if you use
non ASCII characters) files.


Intervall definition
^^^^^^^^^^^^^^^^^^^^
The intervall definition can be found below
'$CCOLLECT_CONF/defaults/intervalls/' or '/etc/ccollect/defaults/intervalls'. 
Every file below this directory specifies an intervall. The name of the file is the
name of the intervall: `intervalls/'<intervall name>'`.

The content of this file should be a single line containing a number.
This number defines how many versions of this intervall to keep.

Example:
-------------------------------------------------------------------------
   [10:23] zaphodbeeblebrox:ccollect-0.2% ls -l conf/defaults/intervalls/
   insgesamt 12
   -rw-r--r--  1 nico users 3 2005-12-08 10:24 daily
   -rw-r--r--  1 nico users 3 2005-12-08 11:36 monthly
   -rw-r--r--  1 nico users 2 2005-12-08 11:36 weekly
   [10:23] zaphodbeeblebrox:ccollect-0.2% cat conf/defaults/intervalls/*
   28
   12
   4
--------------------------------------------------------------------------------
This means to keep 28 daily backups, 12 monthly backups and 4 weekly.

Source configuration
~~~~~~~~~~~~~~~~~~~~
Each source configuration exists below '$CCOLLECT_CONF/sources/$name' or
'/etc/ccollect/sources/$name'.

The name you choose for the subdirectory describes the source.

Each source has at least the following files:

   - `source`       (a text file containing the rsync compatible path to backup)
   - `destination`  (a link to the directory we should backup to)

Additionally a source may have the following files:

   - `verbose`   whether to be verbose (passes -v to rsync)
   - `exclude`   exclude list for rsync. One exclude specification on each line.
   - `rsync_options' extra options to pass to rsync

Example:
--------------------------------------------------------------------------------
   [10:47] zaphodbeeblebrox:ccollect-0.2% ls -l  conf/sources/testsource2
   insgesamt 12
   lrwxrwxrwx  1 nico users   20 2005-11-17 16:44 destination -> /home/nico/backupdir
   -rw-r--r--  1 nico users   62 2005-12-07 17:43 exclude
   drwxr-xr-x  2 nico users 4096 2005-12-07 17:38 intervalls
   -rw-r--r--  1 nico users   15 2005-11-17 16:44 source
   [10:47] zaphodbeeblebrox:ccollect-0.2% cat conf/sources/testsource2/exclude 
   openvpn-2.0.1.tar.gz
   nicht_reinnehmen
   etwas mit leerzeichenli
   [10:47] zaphodbeeblebrox:ccollect-0.2% ls -l  conf/sources/testsource2/intervalls
   insgesamt 4
   -rw-r--r--  1 nico users 2 2005-12-07 17:38 daily
   [10:48] zaphodbeeblebrox:ccollect-0.2% cat conf/sources/testsource2/intervalls/daily 
   5
   [10:48] zaphodbeeblebrox:ccollect-0.2% cat conf/sources/testsource2/source 
   /home/nico/vpn
--------------------------------------------------------------------------------

Detailled description of "source"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
`source` describes a rsync compatible source (one line only).
 
For instance 'backup_user@foreign_host:/home/server/video'.
To use the rsync protocol without the ssh-tunnel, use
'rsync::USER@HOST/SRC'. For more information have a look at rsync(1).
 
Detailled description of "verbose"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
`verbose` tells `ccollect` that the log should contain verbose messages.

If this file exists in the source specification *-v* will be passed to `rsync`.

Example:
--------------------------------------------------------------------------------
   [11:35] zaphodbeeblebrox:ccollect-0.2% touch conf/sources/testsource1/verbose
--------------------------------------------------------------------------------


Detailled description of "exclude"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
`exclude` specifies a list of paths to exclude. The entries are new line (\n)
seperated.

Example:
--------------------------------------------------------------------------------
   [11:35] zaphodbeeblebrox:ccollect-0.2% cat conf/sources/testsource2/exclude 
   openvpn-2.0.1.tar.gz
   nicht_reinnehmen
   etwas mit leerzeichenli
   something with spaces is not a problem
--------------------------------------------------------------------------------


Detailled description of "destination"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
`destination` must be a link to the destination directory.

Example:
--------------------------------------------------------------------------------
   [11:36] zaphodbeeblebrox:ccollect-0.2% ls -l conf/sources/testsource2/destination 
   lrwxrwxrwx  1 nico users 20 2005-11-17 16:44 conf/sources/testsource2/destination -> /home/nico/backupdir
--------------------------------------------------------------------------------


Detailled description of "intervalls/"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
When you create a subdirectory `intervalls/` within your source configuration
directory, you can specify individiual intervalls for this specific source.
Each file below this directory describes an intervall.

Example:
--------------------------------------------------------------------------------
   [11:37] zaphodbeeblebrox:ccollect-0.2% ls -l conf/sources/testsource2/intervalls/      
   insgesamt 8
   -rw-r--r--  1 nico users 2 2005-12-07 17:38 daily
   -rw-r--r--  1 nico users 3 2005-12-14 11:33 yearly
   [11:37] zaphodbeeblebrox:ccollect-0.2% cat  conf/sources/testsource2/intervalls/*
   5
   20
--------------------------------------------------------------------------------

Detailled description of "rsync_options"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

When you create the file `rsync_options` below your source configuration,
all the parameters found in this file will be passed to rsync. This
way you can pass additional options to rsync. For instance you can tell rsync
to show progress ("--progress") or which -password-file ("--password-file")
to use for automatic backup over the rsync-protocol.

Example:
--------------------------------------------------------------------------------
   [23:42] hydrogenium:ccollect-0.2% cat conf/sources/test_rsync/rsync_options
   --password-file=/home/user/backup/protected_password_file
--------------------------------------------------------------------------------


Hints
-----

Using rsync protocol without ssh
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

When you have a computer with little computing power, it may be useful to use
rsync without ssh, directly using the rsync protocol
(specify 'user@host::share' in `source`). You may wish to use
`rsync_options` to specify a password file to use for automatic backup.


Example:
--------------------------------------------------------------------------------
backup:~# cat /etc/ccollect/sources/sample.backup.host.org/source         
backup@webserver::backup-share

backup:~# cat /etc/ccollect/sources/sample.backup.host.org/rsync_options 
--password-file=/etc/ccollect/sources/sample.backup.host.org/rsync_password

backup:~# cat /etc/ccollect/sources/sample.backup.host.org/rsync_password 
this_is_the_rsync_password
--------------------------------------------------------------------------------
This hint was reported by Daniel Aubry.


Not-excluding top-level directories
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

When you exclude "/proc" or "/mnt" from your backup, you may run into
trouble when you restore your backup. When you use "/proc/\*" or "/mnt/\*"
instead `ccollect` will backup empty directories.

[NOTE]
===========================================
When those directories contain hidden files
(those beginning with a dot (*.*)),
they will still be transferred!
===========================================
This hint was reported by Marcus Wagner.

Examples
--------

A backup host configuration from scratch
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

--------------------------------------------------------------------------------
srwali01:~# mkdir /etc/ccollect
srwali01:~# mkdir -p /etc/ccollect/defaults/intervalls/
srwali01:~# echo 28 > /etc/ccollect/defaults/intervalls/taeglich
srwali01:~# echo 52 > /etc/ccollect/defaults/intervalls/woechentlich
srwali01:~# cd /etc/ccollect/
srwali01:/etc/ccollect# mkdir sources
srwali01:/etc/ccollect# cd sources/
srwali01:/etc/ccollect/sources# ls
srwali01:/etc/ccollect/sources# mkdir local-root
srwali01:/etc/ccollect/sources# cd local-root/
srwali01:/etc/ccollect/sources/local-root# echo / > source
srwali01:/etc/ccollect/sources/local-root# cat > exclude << EOF
> /proc
> /sys
> /mnt
> EOF
srwali01:/etc/ccollect/sources/local-root# ln -s /mnt/hdbackup/local-root destination
srwali01:/etc/ccollect/sources/local-root# mkdir /mnt/hdbackup/local-root
srwali01:/etc/ccollect/sources/local-root# ccollect.sh taeglich local-root
/o> ccollect.sh: Beginning backup using intervall taeglich
/=> Beginning to backup "local-root" ...
|-> 0 backup(s) already exist, keeping 28 backup(s).
--------------------------------------------------------------------------------

After that, I added some more sources:
--------------------------------------------------------------------------------
srwali01:~# cd /etc/ccollect/sources
srwali01:/etc/ccollect/sources# mkdir windos-wl6
srwali01:/etc/ccollect/sources# cd windos-wl6/
srwali01:/etc/ccollect/sources/windos-wl6# echo /mnt/win/SYS/WL6 > source
srwali01:/etc/ccollect/sources/windos-wl6# ln -s /mnt/hdbackup/wl6 destination
srwali01:/etc/ccollect/sources/windos-wl6# mkdir /mnt/hdbackup/wl6
srwali01:/etc/ccollect/sources/windos-wl6# cd ..
srwali01:/etc/ccollect/sources# mkdir windos-daten
srwali01:/etc/ccollect/sources/windos-daten# echo /mnt/win/Daten > source
srwali01:/etc/ccollect/sources/windos-daten# ln -s /mnt/hdbackup/windos-daten destination
srwali01:/etc/ccollect/sources/windos-daten# mkdir /mnt/hdbackup/windos-daten

# Now add some remote source
srwali01:/etc/ccollect/sources/windos-daten# cd ..
srwali01:/etc/ccollect/sources# mkdir srwali03
srwali01:/etc/ccollect/sources# cd srwali03/
srwali01:/etc/ccollect/sources/srwali03# cat > exclude << EOF
> /proc
> /sys
> /mnt
> /home
> EOF
srwali01:/etc/ccollect/sources/srwali03# echo 'root@10.103.2.3:/' > source
srwali01:/etc/ccollect/sources/srwali03# ln -s /mnt/hdbackup/srwali03 destination
srwali01:/etc/ccollect/sources/srwali03# mkdir /mnt/hdbackup/srwali03
--------------------------------------------------------------------------------

Using hard-links requires less disk space
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

-------------------------------------------------------------------------
[10:53] srsyg01:sources% du -sh ~/backupdir 
4.6M    /home/nico/backupdir
[10:53] srsyg01:sources% du -sh ~/backupdir/*
4.1M    /home/nico/backupdir/daily.2005-12-08-10:52.28456
4.1M    /home/nico/backupdir/daily.2005-12-08-10:53.28484
4.1M    /home/nico/backupdir/daily.2005-12-08-10:53.28507
4.1M    /home/nico/backupdir/daily.2005-12-08-10:53.28531
4.1M    /home/nico/backupdir/daily.2005-12-08-10:53.28554
4.1M    /home/nico/backupdir/daily.2005-12-08-10:53.28577

srwali01:/etc/ccollect/sources# du -sh /mnt/hdbackup/wl6/         
186M    /mnt/hdbackup/wl6/
srwali01:/etc/ccollect/sources# du -sh /mnt/hdbackup/wl6/*
147M    /mnt/hdbackup/wl6/taeglich.2005-12-08-14:42.312
147M    /mnt/hdbackup/wl6/taeglich.2005-12-08-14:45.588
-------------------------------------------------------------------------