1. Introduction

This CD backup utility allows you to select from a number of backup profiles that you previously defined and uses mkisofs and cdrecord to actually write them to the CD.

It is not intended to be a general purpose interface for burning CD's, for which there are a number of other excellent programs.

1.1 Future directions

This is an initial release, so only has the basic functionality. Improvements would include allowing it to deal with incremental backups and using multi session support to place them onto one CD.

2. Configuration

2.1 Files

First the file /etc/cdbak.conf is read if it exists. Followed by ~/.cdbak.conf and $CDBAK. The contents of these files are merged with the later ones overriding the contents of earlier ones.

2.2 Specifying backup profiles

The configuration file contains a number of backup profiles. These consist of a set of directories to backup and various other parameters that control the backup.

Each section in the file begins with the profile name in square brackets. Following this are a number of parameters that control the backup. For example:

[SYSTEM]
backup:
	dir /boot
	dir /etc
	dir /root
	dir /var

Here we have a profile named SYSTEM that specifies that everything under /boot, /etc, /root and /var will be backed up.

2.2.1 Backup directory list

The word backup is followed by a colon and then all following lines beginning with spaces. The backup item takes a series of dir commands; one per line for each directory that is to be backed up.

2.2.2 Controlling the directory layout on the CD

By default, files are placed on the CD at the same path as they exist on your disk. To change this you can place a second directory name after the first which will become the name that is used on the CD.

#
# In this example, with the following specification, the file /etc/termcap
# would be written on the CD as /new/etc/termcap
#
backup:
	dir /etc /new/etc

2.2.3 Excluding parts of the directory tree

Quite often there will be directories that you know should not be backed up as they contain temporary files or files that can be easily re-created.

You can exclude these with the except command in the configuration file.

[HOME]
#
# In this example everything under /home/steve is to be backed up
# apart from the directories build, tmp and kern.
# Also everything in the .netscape/cache and .netscape/xover-cache
# directories are excluded.
#
backup:
	dir /home/steve, except build, except tmp,
		except kern,
		except .netscape/cache,
		except .netscape/xover-cache

After dir is a comma and then the word except followed by a directory to exclude. This directory is relative to the one given by dir. For example dir /A , except B/C would exclude /A/B/C from the backup. Lines ending in a comma are continued on the next line.

2.3 The DEFAULT section

The default section is special and is not the name of a backup profile. In the DEFAULT section you can place all parameters that do not change from profile to profile. If a parameter occurs in the DEFAULT section and in a profile, then the value in the profile will be used.

output

The file name that the backup is written to. This file will be up to the size of a CD (650MB) and so should be on a partition that has plenty of space.

output: /temp/backup.raw

application_id

This is the name that will be put onto the CD header. You can use it to identify the backup, and in this case it should probably be overridden in each section.

rockridge

Use Rock Ridge format. This should be set to yes unless you have a good reason not to.

rockridge: yes

rockridge_dist

This passes the -r option to mkisofs rather than -R. See the mkisofs documentation for exact details of what it does. Basically this option is more useful for distributing software as all the ownership and file mode information is removed. For you own backups you would usually set this to no.

device

This is the device name that will be passed to cdrecord. See the cdrecord documentation for this.

device: 0,0

speed

The CD writing speed.

speed: 2

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