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Backup
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Overview
========

Backup is used to create a single archive from a collection of files and 
folders. The archive can be in one of two different formats, and a 
number of backup methods are available, as are a number of levels of 
compression. These range from uncompressed if you simply wish to collect 
a number of files together to ultra, which although it takes a long time 
gives maximum compression. 

User Interface
==============

The Backup tab is roughly split into three sections. Along the top are 
the controls for the backup, the standard jobs area, the standard rules 
area and other settings for the backup. On the left hand side below 
these settings if the computer browser. Here you can select which files 
to backup. On the right there are two main areas. Firstly is the backup 
location selector, this is where you can select the location of the 
archive to create. Below this is the file list. Once you have added 
files from the computer browser they appear here so you can easily see 
what will be backed up. Using the buttons on the right hand side you can 
also add Variables and expand all of the folders you have selected. The 
file list is automatically coloured using any Rules you might have 
selected. 

    .. figure:: /images/backup.png
       :align: center
       :alt: The Backup Tab

Function
========

Complete
	This backs up all of the files you have added in the File List to the 
	location specified in the Backup Location. 


Update
	This adds newer files from your File List to the Backup Location.

Differential
	On its first run a base file is created in the folder specified in the 
	Backup Location. In subsequent runs changes files are backup up in an 
	archive named after the date and time. To restore a differential backup 
	you need to restore the base file and then the most recent date file. 
	Currently this only supports one source folder. 


Restore
	Restores files from an archive into a folder. This works the other way 
	on to other the main functions, you add the files to the file list and 
	they are extracted into the folder specified. 

Format
======

Toucan supports two formats currently, they are:

Zip
	An industry standard format with average compression levels and speed. 
	It is ideal to use when you are taking archives to other computers as 
	many operating systems have support for zip archives built in. 

7-Zip
	An improved format developed by Igor Pavlov. It is normally both faster 
	and its archives are smaller than Zip archives. However support is much 
	rarer. 
	
GZip
	When this mode is selected files are firstly added to a tarball before 
	being gzipped. This format is normally used for Linux archives. 

Compression Level
=================

Six levels of compression are supported, from no compression to ultra 
compression. Each increment reduces the size of the final archive but 
takes more time to produce. Please note that ultra many take a *very* 
long time, especially if you are backing up large numbers of files. 

Other
=====

Password
	When this is enabled you will be prompted for a password at the start 
	of the job. Toucan uses the standard encryption systems for both Zip and 
	7-Zip archives. 


Test After Creation
	After the archive is created a test command is run to ensure the 
	integrity of the archive. 


Solid Mode
	This options is only valid for 7-Zip archives. It gives an improved 
	compression ratio at the cost of potentially corrupting a larger part of 
	the archive if there is an issue. 

Preview
=======

Whenever you add new items to a backup job they will automatically be 
previewed and so either be left black, so show they will be included in the 
job, or red to show that they have been excluded. 