CDBKUP(1)CDBKUP(1)NAMEcdbkup - Backup a filesystem to one or more CD-R(W)s
SYNOPSIScdbkup 0-9 [ --help ] [ -1, --single ] [ -a, --append ] [ -b, --blank ]
[ -c, --compress=TYPE ] [ -e, --exclude=PATH ] [ -h, --host=HOST ] [
-I, --no-iso ] [ -l, --label=NAME ] [ -m, --cross-mp ] [ -r, --recycle
] [ -s, --speed=SPEED ] [ -S, --cdsize=SIZE ] [ -t, --test ] [ -V,
--version ] [ -w, --workdir=PATH ] [ -z, --zip-here ] DEVICE DUMPDIR
OPTIONS
0-9 Specify the backup level. See the section on BACKUP LEVELS for
more info.
--help Show usage message and quit.
-1, --single
Burn the last disk in single session mode. Normally, the last
disk is burned in multisession mode, allowing for additional
data to be appended to the end of it. This option has no effect
when used with --append or --recycle, since in these cases, the
burn is always done in multisession mode.
-a, --append
Append the backup onto the end of a multisession disk. If the
disk is empty, then create the first session. When this option
is used, the program runs non-interactively, and the entire
backup must fit in the available space on the disk. Make sure
to insert the correct disk before running the program.
If this option is used in conjunction with --blank (-b), then
the disk is blanked first, and the entire image must fit on the
blank CD. See also --recycle.
-b, --blank
Blank all disks before writing. This option may not be used in
conjunction with --recycle (-r).
-c, --compress=TYPE
Compress using the specified compression format. Possible
options are gz for gzip compression, bz2 for bzip2 compression
or none for no compression. The default is gz.
-e, --exclude=PATH
Excludes the specified file or directory from the backup. This
option may be specified multiple times.
-h, --host=HOST
Specify the hostname whose filesystem is to be backed up. The
CD burner is assumed to be on the localhost. The transfer is
done via SSH, so make sure that the remote machine is running an
SSH server, and that the local machine has an SSH client
installed. If this parameter is not specified, then the local
machine is backed up.
-I, --no-iso
This option can only be used in conjunction with both --test and
--cdsize. It prevents the backup tarballs from being rolled up
into ISO files. See the --cdsize (-S) option for more informa‐
tion.
-l, --label=NAME
Set the backup volume label. If the backup directory is any‐
thing other than '/', then this parameter is required. Other‐
wise, the default volume label is the hostname of the machine
being backed up. To generate the filenames for the CD images,
cdbkup appends three things to the volume label: the current
date, the backup level, and the extension .tar.gz. If the
entire image fits on one disk, then this filename is exact.
Otherwise, a dot and the disk number are appended to the file‐
name on each disk, after the file extension.
-m, --cross-mp
Cross between filesystems when dumping. By default, cdbkup
ignores mount points within the directory tree being backed up.
This option causes cdbkup to include these mount points as
though they were plain subdirectories.
You can use the --exclude option to explicitly exclude mount
points that you don't want, such as /proc and /usb under Linux.
-r, --recycle
Same as --append, except that the disk is blanked first if the
data doesn't fit in the available space. If the data is too
large to fit even on a blank CD, then the CD is not blanked, but
this program returns an error. This option conflicts with
--append and --blank.
-s, --speed=SPEED
Set the burn speed. The default is 2.
-S, --cdsize=SIZE
Specify the size of the output media in bytes. Normally, cdbkup
attempts to autodetect the size of the disk and uses a default
of 650,000,000 bytes if autodetection fails. This option dis‐
ables autodetection.
Unless --no-iso is specified, SIZE must be large enough to
account for both high-level and low-level filesystem overhead.
So you should expect any ISO images to be significantly smaller
than the given value. If --no-iso is specified then SIZE is the
exact maximum filesize.
-t, --test
Do not use the CD-ROM burner. In this mode, the backup proceeds
normally, except that the backup file(s) are saved to the cur‐
rent directory instead of being burned onto CD-R(W)s. The out‐
put is normally a single tarball. If --cdsize is specified then
the output is one or more ISO images. If both --cdsize and
--no-iso are specified, then the output is one or more tarballs.
If -t is used, the following options are ignored: -1, -a, -b,
-r, -s.
-V, --version
Print the version number and exit.
-w, --workdir=PATH
Set the working directory as specified. The default is
/tmp/cdworkdir. Except in the case of remote backups, this
directory is automatically excluded from the backup. (See the
--exclude option.)
-z, --zip-here
For remote backups, perform compression locally. This has the
advantage of decreased CPU load on the remote machine, but the
disadvantage of increased network traffic. This option has no
effect on local backups.
DESCRIPTION
This manual page documents briefly the cdbkup filesystem backup util‐
ity.
cdbkup backs up the filesystem under the specified directory to one or
more CD-R(W)s. It can run either interactively, for large backups, or
non-interactively, for backups that you expect to fit on a single disk.
In interactive mode, the program asks you to insert CDs at the appro‐
priate times, and offers you the ability to retry in case of errors.
In non-interactive mode (using -a or -r), the program expects the tar‐
get CD to already be in the drive. If an error occurs, the program
prints an error message and returns a non-zero status code.
To restore a filesystem, begin with a blank filesystem, and use cdrstr
(1) to restore the most recent backups at each level, beginning with
the lowest level and increasing.
DEVICES
The device specified on the command line is the SCSI device for the CD-
ROM burner. For more information, see the dev= option of cdrecord (1).
BACKUP LEVELS
The range of backup levels (0-9) facilitates a variety of backup
strategies. Level 0 always performs a full backup. Higher-level back‐
ups usually perform incremental backups, and they only save the changes
since the most recent backup of a lower level. So, for instance,
monthly backups could be performed at level 0, weekly backups at level
3 and daily backups at level 5. Thus, the daily backups would only
save changes since the beginning of the week, and the weekly backups
would only save changes since the beginning of the month.
When restoring (using cdrstr (1)), the most recent level 0 backup would
have to be restored, followed by the most recent level 3 backup, then
by the most recent level 5 backup.
It is recommended to use the --append or --recycle options for daily
backups, since many will often fit on the same CD. But for safety, you
should alternate between two or more CD-RWs so that, even in the case
of failure, you still have a quite recent backup.
Note that you can't put more than one backup performed on the same day
of the same filesystem or directory on the same CD-R(W), since the
filenames would be identical. In general, it's unusual to perform
backups more than once per day, but if you must then use a different
CD-R(W).
EXAMPLEScdbkup 0 -e /tmp -s 4 0,0,0 /
Does a full (level 0) backup of the local root directory,
excluding /tmp onto (maybe) multiple CD-Rs, burning at 4-speed.
The CD-Rs must already be blank.
cdbkup 0 -b -e /tmp -s 4 0,0,0 /
Same as above, but blanks all disks (which must be CD-RWs)
before writing the backup images.
cdbkup 0 -h my.webserver.org -e /tmp 0,0,0 /
Does a full backup of a remote webserver, excluding /tmp onto
(maybe) multiple CD-Rs. Compression is performed on the web‐
server machine in order to save on bandwidth.
cdbkup 0 -h my.webserver.org -z 0,0,0 /
Same as above, except that the /tmp directory is included in the
backup, and compression is performed locally in order to avoid
loading the webserver's CPU.
cdbkup 5 -a -e /tmp 0,0,0 /
Does a level 5 incremental backup of the local root directory,
excluding /tmp onto the remaining space on a multisession CD-R.
If the backup doesn't fit, an error is thrown.
cdbkup 5 -r -e /tmp 0,0,0 /
Same as above, but if the backup doesn't fit, blanks the disk,
then writes the backup.
SEE ALSOcdappend(1), cdcat(1), cdrecord(1), cdrstr(1), cdsplit(1).
AUTHOR
John-Paul Gignac <jp@gignac.org>
Mar 6, 2002 CDBKUP(1)
