.TH "cdbackup" "1" "0.6.3" "Stefan Hülswitt" ""

.SH "NAME"

.LP 

cdbackup \- Streaming backup to CD\-R(W)

.SH "SYNOPSIS"

.LP 

cdbackup [\-mvDVX] [\-d \fIdevice\fP] [\-r \fIscsi\-dev\fP] [\-s \fIspeed\fP]

         [\-p \fInum\fP] [\-l \fIsize\fP] [\-a \fIlabel\fP] [\-c \fIcommand\fP]

         [\-\- \fIcdrecord\-options\fP]

.SH "DESCRIPTION"

.LP 

cdbackup is a utility to make streaming backups to CD\-R(W) disks. It's designed to work with any backup tool which writes the backup to stdout (like tar/cpio/afio).

.LP 

\fINOTE:\fR this program REQUIRES that a recent version of \fBcdrecord\fR(1) is present in the PATH.

.LP 

\fIWARNING!\fR When using this program under Linux, be sure not to use dump on a mounted

filesystem. This has a high potential for creating corrupted backups. As of kernel version

2.4.19, this has not been fixed and it may not be fixed at all.

You can read Linus statement about this at <http://search.alphanet.ch/cgi\-bin/search.cgi?max_results=10&type=long&msgid=Pine.LNX.4.21.0104270953280.2067\-100000@penguin.transmeta.com&domain=ml\-linux\-kernel>

.SH "OPTIONS"

.LP 

.TP 

\fB\-d\fR \fIdevice\fP

The device name which is used for reading things like the TOC from a (partly written) media.

.br 

(default: /dev/burner)

.TP 

\fB\-r\fR \fIscsi\-device\fP

The scsi device which is passed to \fBcdrecord\fR(1) (via dev=\fIscsi\-device\fP). Must be given as three, comma seperated number: \fIscsibus\fR,\fItarget\fR,\fIlun\fR.

.br 

(default: none)

.TP 

\fB\-s\fR \fIspeed\fP

The writing speed which is passed to \fBcdrecord\fR(1) (via speed=\fIspeed\fP).

.br 

(default: 4)

.TP 

\fB\-p\fR \fInum\fP

The number of sectors (of 2048 byte) to use for padding (see \fBcdrecord\fR(1) padsize).

.br 

(default: 15)

.TP 

\fB\-X\fR

Enables the use of CDROM XA2 mode in \fBcdrecord\fR(1). By default CDROM mode 1 is used. The default is possibly causing problems during restore on certain kernel version/CDROM hardware combinations at the end of the last session on a media. Sony drives doesn't support CDROM XA 2 mode (see \fBcdrecord\fR(1) \-multi).

.TP 

\fB\-l\fR \fIsize\fP

The media size in megabytes. This value is used to calculate how much data can be stored on the media.

.br 

(default: 650)

.TP 

\fB\-a\fR \fIlabel\fP

A text label to identify the backup set. The first 32 characters of this string are save with the backup.

.br 

(default: "CDBackup Track")

.TP 

\fB\-c\fR \fIcommand\fP

The command which is executed whenever cdbackup needs to request a new media in multi\-disk mode. This command (or script) should prompt the user and return after the recording device is ready again. The command receives one argument, which is the device name passed with \fB\-d\fR. This can be used to issue commands to the device like ejecting the media.

.br 

(default: use internal diskchange prompt)

.TP 

\fB\-m\fR

Enables multi\-disk mode. When the current media is filled, a new media is requested (see option \fB\-c\fR) and the backup is continued. Backups can only be continued to empty media, this means you cannot insert a partly filled media for continuation.

.TP 

\fB\-v\fR

Enables verbose mode.

.TP 

\fB\-D\fR

Enables DEBUG output (probably not usefull for normal use).

.TP 

\fB\-V\fR

Prints out version information and exits.

.TP 

\fB\-\-\fR \fIcdrecord\-options\fP

Pass following options to \fBcdrecord\fR(1).

.SH "EXAMPLES"

.LP 

To create a tar archive of /home and

output it to a 700 MB CD\-R(W) on /dev/scd0 (scsi device 2,0):

.IP 

tar cvf \- /home | cdbackup \-d /dev/scd0 \-r 2,0 \-l 700 \-a "Test Backup"

.LP 

To create a tar archive of /usr and output it to a series (multi\-disk mode) of 650 MB CD\-R(W) on /dev/sr1 (scsi device 1,4,0) with writting speed 12 and verbose output:

.IP 

tar cf \- /usr | cdbackup \-d /dev/sr1 \-r 1,4,0 \-s 12 \-m \-v

.SH "KNOWN PROBLEMS"

.LP 

Certain combinations of CDROM drivers and kernel versions are causing a problem when restoring data. The restore process aborts with an read error close to the end of the session, while the data on the media is perfectly good.

.LP 

All CDR sessions written in track\-at\-once mode (which is unavoidable for multisessions) end in at least two unreadable runout sectors (for additional information refer to the file README.copy from the cdrecord package). As the kernel does some readahead on the device, it stumbles over these unreadable sectors before reaching the actual end of data.

.LP 

Some drivers are reporting to syslog but doesn't pass the error to the application, while others make the application fail. From user feedback, it seems that pure SCSI setups are mostly working fine, while ide\-scsi setups are likely to fail.

.LP  

The author isn't able to provide a full solution, but some hints which may help:

.TP 

1.

Update to a recent kernel.

.TP 

2.

Disable kernel readahead with option \-R when restoring.

.TP 

3.

Increase the padsize with option \-p. Use values >= 128.

.TP 

4.

Use option \-X if your writer supports this (Sony drives doesn't supports this mode).

.LP 

Please contact the author if you can contribute additional information about the problem.

.SH "AUTHORS"

.LP 

Stefan Hülswitt <huels@iname.com>

.SH "SEE ALSO"

.LP 

\fBcdrestore\fR(1), \fBcdrecord\fR(1)

.SH "LICENSE"

Copyright (c) 2000\-2002 Craig Condit, Stefan Hülswitt.

Redistribution and use in source and binary forms, with or without

modification, are permitted provided that the following conditions are met: 

.TP 

1.

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 

.TP 

2.

Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

.LP 

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS

OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR

ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

SUCH DAMAGE.