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       cback - Local and remote backups to CD-R/CD-RW media


       cback [switches] action(s)


       The  cback script provides the command-line interface for Cedar Backup.
       Cedar Backup is a software package designed to  manage  system  backups
       for  a pool of local and remote machines.  Cedar Backup understands how
       to back up filesystem data as well as MySQL  and  PostgreSQL  databases
       and Subversion repositories.  It can also be easily extended to support
       other kinds of data sources.

       Cedar Backup is focused around weekly backups to a  single  CD  or  DVD
       disc, with the expectation that the disc will be changed or overwritten
       at the beginning of each week.  If your hardware is new  enough,  Cedar
       Backup  can  write  multisession discs, allowing you to add incremental
       data to a disc on a daily basis.

       There are two kinds of machines in a Cedar Backup  pool.   One  machine
       (the master) has a CD-R or CD-RW drive on it and is where the backup is
       written to disc.  The others (clients) collect data to  be  written  to
       disc  by the master.  Collectively, the master and client machines in a
       pool are all referred to as peer machines.  There are four actions that
       take  place  as  part  of the backup process: collect, stage, store and
       purge.  Both the master and the clients execute the collect  and  purge
       actions, but only the master executes the stage and store actions.  The
       configuration file /etc/cback.conf controls the  actions  taken  during
       collect, stage, store and purge actions.

       Cedar  Backup  also  supports  the concept of managed clients.  Managed
       clients have their entire backup process managed by the  master  via  a
       remote  shell.  The same actions are run as part of the backup process,
       but the master controls when the actions are executed  on  the  clients
       rather than the clients controlling it for themselves.


       -h, --help
              Display usage/help listing.

       -V, --version
              Display version information.

       -b, --verbose
              Print  verbose  output  to  the  screen  as  well writing to the
              logfile. When this option  is  enabled,  most  information  that
              would normally be written to the logfile will also be written to
              the screen.

       -q, --quiet
              Run quietly (display no output to the screen).

       -c, --config
              Specify the  path  to  an  alternate  configuration  file.   The
              default configuration file is /etc/cback.conf.

       -f, --full
              Perform  a  full  backup,  regardless of configuration.  For the
              collect action, this means that any existing information related
              to  incremental  backups  will be ignored and rewritten; for the
              store action, this means that a new disc will be started.

       -M, --managed
              Include managed clients when executing actions.  If  the  action
              being  executed  is  listed  as  a  managed action for a managed
              client, execute the action on that client  after  executing  the
              action locally.

       -N, --managed-only
              Include  only  managed  clients  when executing actions.  If the
              action being executed is  listed  as  a  managed  action  for  a
              managed  client, execute the action on that client -- but do not
              execute the action locally.

       -l, --logfile
              Specify the path to an alternate logfile.  The  default  logfile
              file is /var/log/cback.log.

       -o, --owner
              Specify  the  ownership  of the logfile, in the form user:group.
              The default ownership is root:adm, to match the Debian  standard
              for most logfiles.  This value will only be used when creating a
              new logfile.  If the  logfile  already  exists  when  the  cback
              script  is  executed,  it will retain its existing ownership and
              mode.  Only user and group names may be used,  not  numeric  uid
              and gid values.

       -m, --mode
              Specify  the permissions for the logfile, using the numeric mode
              as in chmod(1).  The default mode  is  640  (-rw-r-----).   This
              value  will  only  be  used when creating a new logfile.  If the
              logfile already exists when the cback  script  is  executed,  it
              will retain its existing ownership and mode.

       -O, --output
              Record  some sub-command output to the logfile. When this option
              is enabled, all output from system commands will be logged. This
              might  be  useful  for  debugging  or  just for reference. Cedar
              Backup uses system commands  mostly  for  dealing  with  the  CD
              recorder and its media.

       -d, --debug
              Write debugging information to the logfile. This option produces
              a high volume of output, and would generally only be needed when
              debugging a problem. This option implies the --output option, as

       -s, --stack
              Dump a Python stack  trace  instead  of  swallowing  exceptions.
              This  forces  Cedar Backup to dump the entire Python stack trace
              associated with  an  error,  rather  than  just  progating  last
              message  it  received back up to the user interface.  Under some
              circumstances, this is useful information to include along  with
              a bug report.

       -s, --diagnostics
              Display  runtime  diagnostic  information  and  then exit.  This
              diagnostic information is often useful when filing a bug report.


       all    Take  all normal actions (collect, stage, store, purge), in that

              Take the collect action, creating tarfiles  for  each  directory
              specified in the collect section of the configuration file.

       stage  Take  the  stage  action, copying tarfiles from each peer in the
              backup pool to the daily staging directory, based on  the  stage
              section of the configuration file.

       store  Take  the  store  action, writing the daily staging directory to
              disc based on the store section of the configuration file.

       purge  Take the purge  action,  removing  old  and  outdated  files  as
              specified in the purge section of the configuration file.

              Rebuild  the "this week’s" disc based on the current contents of
              the staging directory.  This option has been made available as a
              means  to  recover  a  disc  that  has  been  "trashed" due to a
              hardware or media error.

              Ensure that configuration is valid, but take  no  other  action.
              Validation  checks  that the configuration file can be found and
              can  be  parsed,  and  also  checks  for  typical  configuration
              problems,  such as directories that are not writable or problems
              with the target SCSI device.


       Cedar Backup returns 0 (zero) upon normal  completion,  and  six  other
       error codes related to particular errors.

       1      The Python interpreter version is < 2.3.

       2      Error processing command-line arguments.

       3      Error configuring logging.

       4      Error parsing indicated configuration file.

       5      Backup was interrupted with a CTRL-C or similar.

       6      Error executing specified backup actions.


       The  script  is designed to run as root, since otherwise it’s difficult
       to back up system directories or write the CD or DVD device.   However,
       pains are taken to switch to a backup user (specified in configuration)
       when appropriate.

       To use the script, you must specify at least one action to take.   More
       than  one  of the "collect", "stage", "store" or "purge" actions may be
       specified, in any arbitrary order.  The "all", "rebuild" or  "validate"
       actions  may  not  be  combined  with  other actions.  If more than one
       action is specified, then actions will be taken  in  a  sensible  order
       (generally  collect,  followed by stage, followed by store, followed by

       If you have configured any Cedar Backup extensions,  then  the  actions
       associated  with  those extensions may also be specified on the command
       line. If you specify any other actions along with an  extended  action,
       the actions will be executed in a sensible order per configuration. The
       "all" action never executes extended actions, however.

       Note that there is no facility for restoring backups.   It  is  assumed
       that the user can deal with copying tarfiles off disc and using them to
       restore missing files as needed.  The  user  manual  provides  detailed
       intructions in Appendix C.

       Finally,  you should be aware that backups to CD or DVD can probably be
       read by any user which has permissions to mount the CD  or  DVD  drive.
       If  you  intend to leave the backup disc in the drive at all times, you
       may want to consider this when setting up device  permissions  on  your
       machine.  You might also want to investigate the encrypt extension.


       /etc/cback.conf - Default configuration file

       /var/log/cback.log - Default log file


       There probably are bugs in this code.  However, it is in active use for
       my own backups, and I fix problems as I notice them.   If  you  find  a
       bug,   please  report  it.   If  possible,  give  me  the  output  from
       --diagnostics, all of the error messages that the script  printed  into
       its  log,  and  also any stack-traces (exceptions) that Python printed.
       It would be even better if you could  tell  me  how  to  reproduce  the
       problem (i.e. by sending me your configuration file).

       Report bugs to <>.


       Written by Kenneth J. Pronovici <>.


       Copyright (c) 2004-2008 Kenneth J. Pronovici.
       This is free software; see the source for copying conditions.  There is
       NO warranty; not even for MERCHANTABILITY or FITNESS FOR  A  PARTICULAR